The session has gone green and there's a line of cars behind him. He takes a while to get off and then departs.
@NovaF1Racer: Initially, yes, but then later deferred entry to 2016.
Massa exits the Williams garage and very nearly clatters into Raikkonen. Not the best session for Raikkonen today, he's been a bit of a magnet for other cars so far today.
Another red flag as Gutierrez, who must have walked under about 26 ladders on his way to the track this morning, pulls up not too far away from the pit exit. Very dangerous place to stop and, as that last tweet said, this will create more havoc for those longer runs.
Seeing some TV shots of a massive blister on Rosberg's tyres. Incredible tyre wear on some of these cars.
We're approaching the final ten minutes and the red flag is still out - the session will resume in less than two minutes.
The session is green again by the way. Lots of cars scampering out to collect as much data as possible.
I tell you what, tyres will be a really interesting topic of discussion after this session. Lots of horrible wear on tyres across the grid. Remember, Pirelli changed the compounds after complaints from drivers such as Massa
@DonThorpe: One pit crew. Different engineers for both cars however.
Mark Sutton there, who does our weekly 'Life Behind a Lens' feature.
@JuanC.Parra: Harder to softer.
We're into the final five minutes now.
There's what I was talking about earlier. Incredible amounts of deg on that soft tyre.
It seems the soft tyre is the one struggling the most.
@Bhs746: Well, that would just be a guess, but seems like he's looking ahead to 2015.
@michaeldsouza: as the weather can be so changeable here, I'd have a compromise between the two I think.
Every car that is still running is out on track. Perez missed the whole session and Alonso, Gutierrez and Vergne all stopped on track.
"I don't know if it's the rear left tyre or the floor, but it's not working," complains Grosjean, whose 2014 has just been one issue after another.
Into the final minute of the session.
"Car is not driveable. It's not driveable" complains Kvyat and he's right, he's slipping and sliding all over the track. He's still on the soft tyre so maybe another example of those struggling - he's done 19 laps on those. They look absolutely decimated.
The clock has expired, so drivers will complete their current runs before we see another run of the virtual safety car system trialled here and in Austin.
The drivers are given a warning and then have ten seconds to get down to a delta time, which they must then stick to. They can see the delta on their steering wheel so know what it is they are staying below.
The dark clouds are rolling in so it looks like some rain is in store; potentially a wet Saturday in store here at Interlagos.
The cars are snaking around the circuit for the virtual safety car system. They'll head back into the pits and that's that for today's practice sessions.
Rosberg tops both sessions today - can he keep that up tomorrow and secure the 2014 pole trophy, the first time that award has been handed out? Be sure to join us tomorrow to find out.