12:45 Hello everyone and welcome to AUTOSPORT Live for the penultimate round of the 2009 FIA Formula 1 World Championship.

Since 1940, Interlagos has seen the cream of Brazil's motor racing talent grace its stage. Those early races provided much fanfare and a wish to bring world class motorsport to Sao Paulo. In the 1970s, that wish became reality as Formula 1 arrived for a series of races on the wonderful old five mile circuit with its high-speed sweepers

Following a break in the 80s, when Rio held the grand prix, Interlagos was modified at huge cost and has proudly held the Brazilian GP since 1990 at the current 2.677 mile track that has kept much of the character of the old beast.

Emerson Fittipaldi, Carlos Pace, Nelson Piquet, Ayrton Senna and Felipe Massa have all wowed the partisan crowd at home.

Rubens Barrichello has raced here 16 times in his Formula 1 career and this weekend can send his supporters into overdrive - providing he can score that elusive victory in his home race.

It's the Brazilian Grand Prix from Interlagos and AUTOSPORT Live will cover all the action from the first practice until the podium ceremony.

12:46 Today, we will guide you through the opening practice sessions with minute-by-minute commentary as the teams and drivers begin their build-up to the race.

First practice will begin shortly, with commentary ending 15 minutes after the session has concluded.

Later, at 16:45 GMT, we will return for live coverage of the second practice session. AUTOSPORT Live will end the day with a weekend weather forecast, on the Brazilian Grand Prix weather page.

12:47 For championship leader Jenson Button the aim the weekend is very simple. If the Briton finishes on the podium at Interlagos he can start celebrating a well-earned first world drivers' title - regardless of where team-mate Barrichello and challenger Sebastian Vettel finish.

The chasing pair simply must finish on the podium and hope that Button is as far down the order as possible to have any chance of taking the battle down to the wire in Abu Dhabi.

In the constructors' championship race, Brawn GP have all-but secured the crown. The Brackley-based team need just half a point from Button and Barrichello to give Ross Brawn his first title as a team owner - and that is providing Red Bull finish one-two in the race. The battle between Ferrari and McLaren to finish third continues to provide interest, with just two points now separating the two teams.

World Championship standings, after round 15:                

Drivers:                    Constructors:             
 1.  Button        85        1.  Brawn-Mercedes        156
 2.  Barrichello   71        2.  Red Bull-Renault      120.5
 3.  Vettel        69        3.  Ferrari                67
 4.  Webber        51.5      4.  McLaren-Mercedes       65
 5.  Raikkonen     45        5.  Toyota                 54.5
 6.  Hamilton      43        6.  Williams-Toyota        34.5
 7.  Rosberg       34.5      7.  Renault                26
 8.  Trulli        30.5      8.  BMW Sauber             24
 9.  Alonso        26        9.  Force India-Mercedes   13
10.  Glock         24       10.  Toro Rosso-Ferrari      5

12:49 Over the last 18 hours, the prospect of Friday rain has decreased slightly, so we start the weekend today with a dry track and overcast skies, but with the light rain we predicted now set for later in the day - possibly towards the end or just after the conclusion of second practice.

The maximum temperature will reach 20 degrees this afternoon and the teams will be keen to get in a full dry day of running so that they can complete their planned programmes of set-up, tyre and fuel load comparisons.

12:51 AUTOSPORT forum members are invited to join the fun throughout the weekend, offering thoughts and opinions as the event unfolds.

• Will Jenson Button clinch the title this weekend, or can Barrichello or Vettel produce a stunning display to carry the fight on to the final round in Abu Dhabi?

• Who do you think will be in good shape here? Power, and KERS assistance, will obviously be a factor exiting the Juncao and pulling up the hill towards the start-finish line, but you also need a good car in the twisty infield section. Who has the best combination to win here?

• Romain Grosjean is under severe pressure to get a result here. Can he produce an error-free weekend and finish well in order to save his short-term Formula 1 future?

Tell everyone what you think.

Click the SHOW LIVE FORUM link in the red bar at the bottom of your browser window if you would like to join the debate.

12:53 With FOTA intending to scrap KERS for next season, this weekend could be one of the final opportunities for the energy recovery system to influence the outcome of a race.

While the high altitude of Interlagos will dent the performance of the engines, the electrical-powered boost from KERS will remain around 80 horsepower. This could prove a major advantage for the McLaren and Ferrari drivers, helping them blast out of Juncao, up the hill and past the pits - aiding both single lap speed and overtaking in the race.

With the likes of McLaren also proving strong in slow corners, much like the twisting infield here, look out for the KERS cars getting right in the mix with the championship contenders.

12:55 First practice for the Brazilian Grand Prix gets underway in five minutes.

12:57 Some of the drivers are already strapped into their cars awaiting the start of the session. Giancarlo Fisichella, Kamui Kobayashi and Kimi Raikkonen are all being readied for action.

12:59 Rubens Barrichello climbs aboard his Brawn Mercedes, while another local hero, Felipe Massa, is speaking with some members of the press in the paddock. It is nice to see him back in familiar surroundings.

12:59 Fernando Alonso climbs aboard his Renault, getting ready for the session.

0 min: The practice session is underway.

0 min: The track temperature is just 21 Celsius under heavily overcast skies.

1 min: The drivers head out onto the Interlagos circuit for the standard installation laps.

2 min: Giancarlo Fisichella leads the charge back into the pitlane. He is followed by Nick Heidfeld and Sebastian Vettel.

2 min: Robert Kubica heads around for a second installation lap in his BMW as the others head back to the pits.

2 min: Nick Heidfeld is also completing a second tour, as is Jenson Button.

3 min: Rubens Barrichello is yet to run, but team-mate Button crosses the start-finish line to begin a second lap.

3 min: We expect a double-lap installation run here from the Briton.

4 min: Lewis Hamilton completes his installation lap, heading back to the McLaren garage.

5 min: Button comes back into the pits at the end of that second lap, and immediately the Brawn team simulate a front wing change on the car.

7 min: The Brawn cars are sporting some additional sponsorship decals this weekend. Button comes out and is into a fourth lap of the circuit - possibly a timed lap here.

8 min: An interesting change of early session strategy here from the Brawn team. Button comes back into the pits after another two-lap run. He does not set a time.

9 min: Robert Kubica is moved from his seat on the toolchest at the back of the BMW garage, with a mechanic needing access to the tools. The Pole is clearly in no hurry to head out this morning.

9 min: So, to confirm, Button completed a two-lap installation run, then pitted, had a front wing change, and then completed a further two slow laps.

10 min: Toro Rosso drivers Sebastien Buemi and Jaime Alguersuari are both on track now. Alguersuari posts the first time of the weekend - 1m24.099s.

12 min: Alguersuari lowers his time to a 1m20.385s, but immediately Buemi is two seconds quicker and sets 1m18.382s on his first timed lap.

12 min: Despite the threatening skies overhead, there is little urgency within the teams to run early in this session.

13 min: Alguersuari replies with a lap of 1m18.205s to briefly retake the top spot.

13 min: Buemi's second timed lap is 1m16.244s as this game of tennis continues between the Toro Rosso drivers.

15 min: Some light spots of moisture are now falling over the circuit as the Toro Rosso drivers continue on their first run of laps.

15 min: No real rainfall yet and conditions are fine for dry times. To emphasise the point Buemi lowers the benchmark to 1m14.689s.

17 min: Bridgestone has its super-soft and medium compound dry tyres on hand this weekend.

17 min: Kimi Raikkonen has joined the track for some laps in his Ferrari.

17 min: Rubens Barrichello heads out onto the circuit in the Brawn, as Buemi takes another tenth of a second off his best time - 1m14.513s.

18 min: Barrichello crosses the line to begin his first timed lap of the weekend.

18 min: Raikkonen slots in slowest of the three drivers to have set a time so far.

19 min: The Meteo France rainfall radar that the teams use is showing one or two very light showers just moving into the vicinity of the circuit.

20 min: Sebastien Buemi has lowered the target time once again to 1m14.091s as an impressive first run continues. He has improved consistently so far.

20 min: Kimi Raikkonen moves up to second with a 1m14.662s as Heikki Kovalainen slots in third with his early effort.

21 min: Rubens Barrichello completed a sedate first timed lap - 1m17s but he has since moved up to third spot with 1m15.201s.

22 min: Buemi pits at the end of a very decent first run of laps. Seven timed tours there for the Swiss driver.

22 min: Raikkonen is the next man to top the standings with a 1m14.021s effort.

22 min: Mark Webber goes fourth in the Red Bull Renault. 1m14.989s puts the Australian just under one second off the leading pace.

24 min: Lewis Hamilton joins the rush on to the circuit, despite the continuing drizzle.

24 min: More spots of rain are now falling over the circuit. This could briefly affect the dry running as this light shower passes over.

25 min: Mark Webber shows that dry times are still possible for the moment as he goes quickest with a lap of 1m13.951s.

25 min: Hamilton challenges the benchmark immediately, setting the fastest middle sector en route to the quickest time so far - 1m13.631s.

26 min: Jenson Button has now put a time on the board. The championship leader is seventh so far with Barrichello three-tenths quicker in fifth.

27 min: Fernando Alonso is one of the first victims of the slippery conditions, locking up and running wide at Bico de Pato, on to the grass.

27 min: Despite the tricky conditions, Hamilton has lowered the best time further to a 1m13.293s.

27 min: Button moves ahead of Barrichello into fifth spot with 1m14.278s and seconds later Adrian Sutil goes sixth in the Force India.

29 min: Kamui Kobayashi runs wide at the Mergulho, the quick downhill left-hander. He makes it onto the painted asphalt but saves the moment well.

30 min: Hamilton continues on an impressive first run, again setting the quickest time at 1m13.187s.

30 min: Kobayashi is of course replacing Timo Glock at Toyota this weekend. The German is still not well enough to race following his crash in Japan.

31 min: The Brawns are moving up the order as Mark Webber moves into second spot in the Red Bull. Button is third and Barrichello is fourth as this frantic opening spell continues.

32 min: Lewis Hamilton leads the way after 32 minutes of opening practice with a lap of 1m13.187s. He is followed by Webber, Button and Barrichello.

33 min: Light rain continues to fall on the circuit, but slick tyres are still providing enough grip for times to improve.

33 min: The changes continue thick and fast as Barrichello now moves to the front with 1m13.121s as the light spots of drizzle continue.

34 min: Sebastian Vettel is in the mix well in the early stages here. The German goes fourth with 1m13.191s.

34 min: Nico Rosberg and Romain Grosjean have both sampled the run-off area at Descida do Lago as the circuit becomes slippery.

34 min: Sebastian Vettel surges into first place with 1m12.932s ... and then only just manages to slow down for the Senna S.

35 min: Vettel makes it round the opening complex of corners but the rain is getting heavier and that's it for dry times for the next few minutes at least.

36 min: Jenson Button is one of the last back into the pits at the end of that first run.

37 min: Sebastian Vettel just managed to sneak in that 1m12.932s lap before the heaviest of the rain came. Barrichello is second.

38 min: So the two title challengers have started the weekend brightly. Lewis Hamilton is third, with Webber fourth, Button fifth and Buemi sixth.

39 min: All drivers are in the pits at the moment as this light rain continues to fall over Interlagos.

40 min: There will be little urgency to head out in these conditions as the teams will want to conserve their wet-weather tyres.

40 min: Continuing the rundown of the top ten, Trulli is seventh, with Adrian Sutil eighth, Nico Rosberg ninth and Fernando Alonso in tenth spot.

41 min: Each driver is limited to four sets of intermediate tyres and three sets of of full-wet tyres for the entire weekend in an effort to reduce the cost of hauling the wet rubber around the world, when often it is not called into action.

44 min: With the forecast of rain possible across all three days at Interlagos, the teams will be particularly keen to limit their tyre use so early in the weekend.

45 min: Sebastian Vettel is back in his car as the mechanics work around the Red Bull, but in the distance we hear music as Alguersuari comes out.

45 min: The Spaniard is out there using a set of intermediate tyres.

47 min: Track conditions aren't particularly conducive for the intermediates. There is very little water on the track, and sure enough, Jaime pits.

48 min: This is a nightmare scenario for the teams. They want to get serious work done, but it's too damp for slicks and too dry for the intermediates.

50 min: Jenson Button is staying in his Brawn, but without his helmet on. He is playing with the settings on his steering wheel while he waits.

51 min: The rain has eased off to a light drizzle in recent minutes.

52 min: Heikki Kovalainen is heading out to sample the grip levels on slick tyres.

53 min: Kovalainen practices a start at the end of the pit exit road and begins an exploratory lap.

53 min: The rest of the field will be eagerly watching Kovalainen to see if the track is ready for dry running again.

53 min: Heikki crosses the line and heads into a timed effort on his dry tyres.

55 min: Despite some minor wobbles on the slippery kerbs, Kovalainen completes a flying lap in 1m15.947s, three seconds off the pace.

55 min: Much of the water seems to have dried from the circuit and dry running should resume in earnest shortly.

55 min: Nico Rosberg has seen enough of Kovalainen's run to head out and check the track conditions for himself.

56 min: Kovalainen improves to 14th with his best lap of the session, indicating that the track is getting back to full speed.

57 min: The session has been stopped.

57 min: Romain Grosjean is out on the circuit ... and runs wide at the Mergulho smashing into one of the polystyrene brake marker boards!

58 min: Lewis Hamilton was ready to head out as the red flag was called and now needs to be recovered to the McLaren garage.

59 min: Kimi Raikkonen tours back into the pits while the clean-up of Grosjean's incident gets underway.

59 min: Grosjean wiped out the 100m braking marker and the track is now being cleared. Meantime ... it's raining again.

59 min: The time continues to count down during this red flag period.

60 min: Grosjean successfully made it back to the pits, but his front wing was broken. Several marshals are now jogging slowly towards the debris.

61 min: The brushing up now begins at the approach to the Juncao. This will take a few minutes to clean up properly.

62 min: Bin bags and brushes are widespread as more marshals arrive to help clean up the many small bits of polystyrene.

63 min: While they clean up, the latest brief shower has passed over. The track is almost dry.

64 min: Between the early flurry of laps, rain and now this Grosjean incident we've had an interesting start to the weekend. Frustrating for the teams of course.

65 min: The session will restart in just a few seconds.

66 min: The session has restarted.

66 min: Jenson Button, Mark Webber and Jaime Alguersuari come out immediately with dry tyres bolted on to their cars.

67 min: Suddenly most of the field are out there. They are eager to play catch-up and continue their work.

67 min: With rain even more likely for second practice, these final 22 minutes could be very busy, despite track conditions being far from ideal.

68 min: Kazuki Nakajima joins the throng on track and he is taking the super-soft tyre for this next run of laps.

68 min: The track temperature is 25 Celsius, with conditions slightly brighter overhead for the moment.

69 min: To remind you, Vettel leads the pack at the moment with Barrichello second, Hamilton third, Webber fourth and Button in fifth.

69 min: Most of the drivers are now out to continue an evaluation of the harder tyre.

70 min: Adrian Sutil is the only driver left in the pits ... in fact, he comes out now and we have all 20 cars on the circuit.

71 min: For just a moment the sun briefly appears, but beyond Mergulho and Juncao we can see another band of heavy cloud approaching the circuit.

72 min: Kimi Raikkkonen improves to seventh quickest, recovering from a moment under braking at Juncao on the previous tour.

72 min: Kazuki Nakajima uses those softer tyres to good effect and posts the fifth fastest time - 1m13.273s.

72 min: Lewis Hamilton improves his time to a 1m13.146s but remains third quickest behind Vettel and Barrichello.

73 min: Jaime Alguersuari improves to 14th place in the Toro Rosso, but is immediately demoted as more drivers set quicker times.

74 min: Nico Rosberg is also using the super-soft tyre for this latest run and he moves up to fourth place with 1m13.147s, as team-mate Nakajima goes third - 1m13.067s.

74 min: Hamilton moves ahead of Barrichello and just over a tenth off the benchmark as team-mate Heikki Kovalainen improves to 11th.

75 min: Adrian Sutil brings back power-sliding memories of the 1970s as he dances his way through the infield at the Ferradura. Wonderful to watch.

76 min: Mark Webber is pressing on in his Red Bull and is now the fastest man in 1m12.805s.

77 min: Rubens Barrichello has spun harmlessly in the infield as he attempted to move up from sixth. He recovers to the pits.

77 min: Sebastien Buemi has crashed his Toro Rosso, damaging the right rear suspension.

78 min: The Swiss driver lost control at the Laranja and backed the STR 4 into the wall. His car is now being lifted away to safety.

79 min: The yellow flags for Buemi has slowed that rush of times, as has another light rain shower.

80 min: Fernando Alonso has been off track at the Senna S as the Spaniard locked up and ran wide, perhaps caught out by the fresh fall of drizzle.

81 min: Light drizzle is falling once again as this amazing session continues. There is action everywhere you look at the moment.

82 min: Buemi's Toro Rosso is now over the barrier and the fast laps can continue once again - providing the drivers can keep the cars on the road.

83 min: Nico Rosberg is still out there with that set of super-soft tyres on the Williams. He is seventh in the standings and has completed 22 laps.

83 min: Sebastian Vettel is now on a hot lap, setting the fastest first sector time. It's a Red Bull one-two at the moment.

84 min: Vettel is not able to beat team-mate Webber. He remains in second spot with Hamilton third, Nakajima fourth and Kovalainen in fifth.

84 min: Nick Heidfeld is out to sample the super-soft rubber on his BMW.

85 min: Vettel's quick lap was spoiled by a slowing Fernando Alonso who came into the pits. The Red Bull pilot is trying again on this current lap.

87 min: The rain has reduced to just the odd spot here and there. Vettel came into the pits, aborting that latest lap but Webber is hammering on.

87 min: Heidfeld continues his move up the order on the softer tyres, going 12th.

88 min: Mark Webber extends his advantage at the top with 1m12.463s using the super-soft tyre. Barrichello comes up into second spot behind him.

88 min: Barrichello's lap was a 1m12.900s with Vettel now third and back in the pits.

88 min: There is heavy traffic on the circuit for this late scramble.

90 min: The session has ended. Cars that have already started a lap may complete it.

14:30 Rubens Barrchello set his best time just before the flag came out, moving to just over four tenths off Webber's session-topping time.

14:31 Heiki Kovalainen jumps up to fourth quickest with a late effort of 1m12.989s.

14:31 Force India drivers Liuzzi and Sutil were having a real adventure on their last run. Liuzzi ran wide running down the hill at Mergulho and continued. Moments later Sutil ran wide onto the kerb at Laranja, which gave him a snap of oversteer.

14:32 Jenson Button ended up seventh after a late lap, but the championship leader looked far from happy with the handling of his Brawn.

14:32 Mark Webber ends the first session on top at Interlagos with a time of 1m12.463s. Barrichello was second, with Vettel third.

14:33 Heikki Kovalainen wound up fourth ahead of McLaren team-mate Lewis Hamilton. Kazuki Nakajima was sixth with Button in seventh place.

14:33 The drivers are heading around to practice starts from the grid.

14:35 Despite the showers, the incidents and one red flag stoppage, every driver completed at least 21 laps. It was certainly entertaining.

14:37 Our round-up of first practice is now available:

Webber tops first practice at Interlagos

14:40 So it's Red Bull at the top with Brawn chasing and McLaren in the mix with their magic KERS. Williams are up there with a super-soft tyre run, but it could all change this afternoon.

Further showers and light rain is expected later. Will we see any dry running later? Join us at 16:45 GMT for practice two from Interlagos.