Welcome back to ESPNF1's live coverage of Friday practice for the Brazilian Grand Prix. Lewis Hamilton was fastest in an FP1 session clouded by 2013 tyre analysis, but hopefully we'll get a more clear picture of the pecking order this afternoon

We learnt after FP1 that the 2013 tyres being used were the same compound as the 2012 hards but that they were 1kg heavier and warmed up more quickly. That seemed to help McLaren a touch, with Hamilton and Button - 1st and 4th - setting their best times on next year's tyres while Vettel and Webber in 2nd and 3rd were quicker on this year's hards

It was a very close session, though, with just 0.086s covering the top four, and Alonso in fifth ending the session 0.216s slower than the quickest time

We had a couple of driver announcements before FP1 started and then saw Valtteri Bottas and Giedo van der Garde - two drivers hoping for seats in 2013 - on track, but they hand their cars back to Bruno Senna and Heikki Kovalainen respectively for FP2

We had a lot of comments and opinions on the battle for the drivers' championship during the first session, and while we may not be able to publish quite as many this afternoon we would still love your comments. So either email us using the link above or tweet us @ESPNF1

The session gets under way in just over ten minutes and could be the last dry running the teams get this weekend. Saturday looks set to be hit by thunderstorms at some point, and Sunday's current forecast is for persistent rain

Shantanu emailed us after FP1 to ask: "You just mentioned in FP1, Alonso did a constant speed the run towards turn four. Whats its significance and how does it helps? Please clarify."

Alonso will have carried it out to get data on the airflow over the 2013 tyres at a constant speed, making it easier to analyse. Paul Hembery said the new tyres would affect the aerodynamics of the cars

It is hot out there. Temperature is up to 33C and track temperature is climbing to 49C

David emails in to ask: "I'd presume that the new tyres would be good for Ferrari who often seemed to have trouble getting this year's tyres up to the right temperatures."

If we were using those tyres on these cars, yes, but the teams are all getting to run them today in order to have the data to base any changes on next year's cars around.

Rod emails in from Canada to say: "Well I sure like to see Lewis on form. One comment, I totally disagree with Ferrari and their decision to open Massa's gearbox last race @ Austin to help Alonso. Let Alonso Race fair and square, so I am going to pick Lewis for the Race Win this weekend ( awesome wet weather driver ) and Seb for the World Title."

We're going to avoid an argument on the rights and wrongs of Ferraris move last weekend, but for the neutral it's a good thing the title is as close as possible heading in to the last race

FP2 begins with Grosjean and Ricciardo heading out first

We're expecting a 'normal' FP2 session with the teams running both compounds of tyre and carrying out long runs later

The Pirelli graphic shows the tyres available this weekend: Medium, Hard, Intermediate, Wet. I reckon it will be the latter two that we're talking about the most over Saturday and Sunday

Rubens Barrichello's in the paddock again, as he was in Austin. This was the scene of the last of his 322 grands prix starts last year

Grosjean with the fastest early time with a 1:16.070, half a second clear of Raikkonen and Ricciardo

Webber goes fastest with a 1:16.000

Abhishek asks: "Can we expect Kovalainen to move to Marussia? Any possibility?"

Afraid not, Abhishek. Marussia needs money from its second driver and Kovalainen has said he won't go out and look for a sponsor

Maldonado runs very wide at turn four after locking up the inside left

Hamilton goes fastest with a 1:15.893

RACE ON! Well, kind of. Vettel dives down the inside of Alonso at Murgulho, with Alonso having let the Red Bull through. Vettel felt he was held up a little though and half raises his hand

Massa goes quickest with a 1:15.473

Everyone running on hard tyres during these early stages

For reference, the quickest time of FP1 was Hamilton's 1:14.131

Hulkenberg radios in to complain of a lack of grip from the rear tyres, It could be that they're overheating with track temperature up at 48C

Alonso is running directly ahead of Vettel on track. Both slow in the final sector before accelerating up the hill towards the start/finish line

Alonso goes quickest with a 1:15.274, but Vettel then crosses the line behind him with a 1:15.226. Just 0.048s between them

Vrijilesh asks: "Think Kobayashi has a shout in at Force India to partner di Resta?"

It's a possibility, but both Hulkenberg and Sutil did have a main sponsor that would help, and Kobayashi doesn't appear to have that in place for 2013

Button goes second with a 1:15.256 - 0.030s slower than Vettel

Sam Michael has been talking during the break between sessions and he said that the 2013 tyre offered some more performance. It's a faster tyre but not by a lot, while McLaren's focus was on how it affects the rest of the car rather than lap time. Data collection was the aim.

Michael also said that McLaren is indifferent on whether it's a wet or dry race. He's happy its wet weather issues are solved from earlier in the year, and says the team is looking to get a one-two to secure second in the constructors' but is aware it will be difficult.

Preetam emails in to ask: "Any news on karthikeyan…will we see him next session?"

Initially I thought this meant next season, but it's a valid question either way! This session: yes the HRTs should get out on track at some point but again it will be running a reduced programme due to a lack of spare parts.

With regards to next season; I believe it would be a choice between Karthikeyan and Ma Qing Hua for the second seat at HRT should the team find a buyer for 2013. Unfortunately, that's looking far from certain.

Only Grosjean and Petrov on track at the moment

Grosjean is cruising around at present, he's not setting lap times

Vergne is out on the medium tyres for Toro Rosso

Vergne was 2.2s off the pace on the hard tyres but he finds 1.1s on the medium tyres

Raikkonen locks up in to turn one and runs wide on to the concrete run-off

Massa sets his fastest first sector but then runs wide on to the kerb at Ferradura and backs off

Perez locks up in to turn one and fails to make the apex, while Webber had also locked up but got away with it

Webber does the fastest middle sector but only goes fourth quickest with a 1:15.336

Glock improves on the medium tyres to a 1:17.845

Travis asks: "What are the chances that Kovalainen gets a seat for next season with Force India, or any team?"

I think Kovalainen could stay at Caterham, but only if the team can somehow overhaul Marussia for 10th in the constructors' this weekend. If that doesn't happen I think he'll be out of a seat and Force India would be his only real option but he'd be competing with Sutil, Bianchi, Kobayashi and Alguersuari

Rosberg goes fifth ahead of Hamilton, just 0.151s slower than Vettel

Alonso does the fastest middle sector but can't improve

Siddhesh says: "I know these times don't mean too much, but its great to see Mclaren/Redbull/Ferrari/Mercedes all separated by .25sec."

Agreed. So close at the front.

Shots of Ross Brawn and Martin Whitmarsh talking in the paddock. Wonder what the topic of conversation is there?

Alonso is again 0.1s up through the first two sectors and this time he carries it through to the end to go fastest by 0.076

Grosjean on the medium tyres now and he locks up slightly in to turn one

Grosjean goes second with a 1:15.182 on the mediums, although he passed a yellow flag

Button takes a lot of kerb at Laranja and has to catch the rear to prevent a spin

HRTs are now on track, which is good to see

Karthikeyan's first timed lap is just 0.2s slower than Pic's best so far

Grosjean improves on his second timed lap and goes fastest with a 1:14.994

Raikkonen goes sixth with a 1:15.371 on medium tyres

Rod asks: "Who do you see as Race Winner and World Champ ? Prediction/Opinion Please."

I've tipped Hamilton to win the race in the preview and also said that means Vettel will be champion with Alonso unable to take maximum points

Alonso struggling on the hard compound as he slides wide at Pinheirhino - the same corner Massa spun at this morning

Mehul asks: "What is the difference between the two compounds?" It looks to be somewhere around 0.8-1s based on the few runs we've seen so far

Rakesh says: "I'd love to see Kovalainen go to Lotus next season. Lotus could do well with two fantastic drivers who have mature heads on their shoulders, plus a Finnish pairing would be nice."

Robin asks: "What exactly paydrivers means in F1...are they responsible to bring sponsors with them and are they even get paid by their team???"

Exactly that, Robin. The term pay driver means they bring money to the team through a personal sponsor - such as Maldonado being backed by PDVSA, and PDVSA paying Williams £30m per year. I don't believe they are paid by the team other than expenses, with their personal sponsorship deals and endorsements making up their wage

The field is so close here that Petrov is just 1.1s off the best time having done a medium tyre lap in the Caterham

Rosberg sets the fastest first sector on the medium tyres

Rosberg goes quickest with a 1:14.822 including the fastest first and last sectors

Hamilton and Massa both on medium tyres now, and Massa goes quickest with a 1:14.553

Hamilton is flying, fastest first sector, fastest middle sector, and fastest overall by half a second with a 1:14.026

Hamilton gets feedback on where he was quickest and how close he was in sector three, then goes and sets the fastest first sector again

Hamilton pits as Webber goes second - 0.497s slower than Hamilton

Webber was on the medium tyres too. Massa tries to get a second lap out of the tyres but is 0.7s off the pace

Webber improves his first sector on his second timed lap but can't improve overall as the tyres appear to drop off a touch

James asks: "If Alonso had Adrian Newey as his designer would he be emulating Schumacher's Ferrari career?"

If Vettel wins the championship this weekend you could argue he's emulating it but just with a different team. Only Fangio and Schumacher have won three world titles in a row

Alonso on the medium tyres has a poor final sector and is almost 2s off the pace

Vettel starts a flying lap on medium tyres and sets the fastest first sector

Vettel loses time compared to Hamilton in the middle sector and is over a quarter of a second slower than Hamilton at the end of the lap

Alonso goes for another flying lap. He's 0.4s down through the first two sectors and ends the lap 0.566s slower than Hamilton in fifth place

Paul emails in to ask: "Any evidence of KERS or alternator related concerns in the Red Bull garage?"

No such issues, though Vettel needed his water level topping up before his latest run. Not a big issue, though

Kobayashi runs wide at turn two and bounces over the kerb

Vettel returns to the pits as Hamilton heads out. The last 25 minutes or so will be mainly heavy fuel running

Hamilton is told on the radio that a 1m19s to a 1m19.5s is expected to be good on his current fuel load

And Hamilton does a 1:19.587...

Pic is rolling very slowly at Pinheirinho and has parked it on the outside of the track

It looks like Pic is stopped in fifth gear, and he's now abandoned his car on the outside of the corner

Webber is following Hamilton with the rain light on the McLaren flashing

Massa does a practice start as he comes out on to the track

Pic's car is stuck in gear and appears to need a crane to move it as two marshals can only rock it on the spot

Raikkonen radios in to say: "Can you see that my tyres are overheating? I've got absolutely no grip front and rear"

The crane is on the scene to get rid of Pic's car, so hopefully we'll be green again soon. Still every car on track except the HRTs and Pic

Schumacher does a 1m19.8s

Vettel does a 1m19.7s - looking quite close at present

Massa runs a bit wide at Murgulho and kicks up dust and dirt on the kerb

Vettel's next lap is a 1:20.003, so the tyres might be struggling to hold on in this heat

Button does a 1m19.5s, as does Grosjean, while Alonso is on the hard tyre

Alonso does a 1:19.929 on the hard tyre

Pic's car has now been cleared, and Glock and Kovalainen scrap for track position in to turn one

This time a 1:19.959 for Alonso, so he's consistent on the hards

Paul asks: "Why are drivers allowed to cut over that white double line at the Interlagos pit entry when they are on flying laps/racing? Is that legal? It seems they get very close to that divider while at top speed!"

It's just the racing line though there, otherwise it makes the corner a real left hander. The extended white line marks where the pit entry is as the barrier makes entry blind but drivers are allowed to cross it on track

An email in just said: "With the top 6 teams being so close, I guess the qualifying results could make all the difference on race day…"

It would normally, but with a wet qualifying and race expected then qualifying becomes a bit less crucial!

Hamilton does a 1m19.3s, while Rosberg is told that he's getting high engine temperatures

Massa with a lock-up on the inside right tyre

Alex asks: "How difficult will overtaking be compared to other circuits and do you think this will be key because of the short circuit to the championship considering Toro Rosso's "strategy" ?"

The track is tough to overtake on, but DRS can help if its dry. All the forecasts say it will be wet though, so overtaking shouldn't be an issue at all

Hamilton does a 1m19.4s, Alonso and Webber both do 1m19.9s and Vettel does a 1m20.3s

If (and it's a big if) these long run lap times are relevant on Sunday then Ferrari will be encouraged as Alonso does a 1m19.5s

Massa with a 1m19.4s as his fuel burns off but his medium tyres start to lose grip

Vettel and Webber both do 1m20.1s on the medium tyres

Button locks up at Laranja and aborts his final lap, while Vettel has a long lock-up in to Bico de Pato

Vettel finishes with a 1m20.1s, so not only did Hamilton have the edge over one lap but he also had it on the long runs too

Of course, with rain forecast Red Bull may be looking at different set-up options, but based on the long runs McLaren looks quickest in the dry and Ferrari, Lotus, Mercedes and Force India not far off.

I know I keep coming back to it, but the expected rain means those long run times may not be relevant come race day. In qualifying, however, Hamilton looks in best shape and you'd have to say we're looking at another battle between Hamilton and Vettel for pole.

An interesting moment at the end of the session, Hamilton radioing in to say that there was a man stood on the track not behind a barrier at turn one, and onboard footage showing that he's only a few feet away from the cars approaching turn one. It appears to be a marshal who just wants to get a bit closer to the action, but he may be facing a slap on the wrists!

So that brings Friday's running to a close, and we'll have all the reaction from the teams and drivers here on ESPNF1.com so stick with us. We'll also be back with live commentary of FP3 at 11am local time tomorrow ahead of the final qualifying session of the season. Join us then.