@ttttt: All mediums, we won't see soft tyre runs until FP2 later this afternoon when the qualifying simulations occur in the cooler temperatures.
@Andreas: I'm not sure yet whether his lock-up was on the lap which put him first or the lap after that. I think it was the latter as he lost a fair chunk of time.
Ericsson moves into 15t5.
Hulkenberg the latest man to run deep into Turn 10. That one always catches me out on the F1 games, so you know it must be difficult.
Hulkenberg being told he needs to push the yellow button before Turn 10, which likely transfers the brake bias to the rear of the car. But he complains the front is lost before the corner anyway.
Rosberg runs across the sand at Turn 11.
Vettel is back out on track.
Vettel is running quite slowly out there - remember he complained about a loss of power earlier in the session. "Slow down, Sebastian, slow down, problem is still there," Ferrari tells him. But Ferrari tells him to stay out so it can check the data.
He did suddenly pick his pace up in the latter part of that lap so maybe Ferrari sorted the issue in the moments after that message, which is usually broadcast on a delay.
@Andreas: Raikkonen's problem hasn't been Sunday, it's been Saturday. If he gets a clean qualifying and gets ahead of Vettel you'd expect him to at least be good for a podium.
Raikkonen has joined Vettel out on track.
@cyrus619: It seems Merc is focused more on its longer runs than setting headline times.
Verstappen the latest to run wide at Turn 11 after suffering a bit of understeer.
Looks like Hamilton's programme has finished ten minutes before the end of the session.
Raikkonen currently three tenths up on his current flying lap.
Bottas is called into the pits for a front wing change, which means Williams are doing some aerodynamic work in this session.
Vettel goes P1 with a 1:38.029...
...but Raikkonen jumps ahead of him immediately by two tenths.
@LawrenceEllul: Absolutely. If this was held at the traditional time it would be another big opportunity for Ferrari.
Mercedes seemingly happy to do its own thang.
@stekay: Indeed, it's one of the big strengths of the SF15-T.
@Oliver: No specifics, but you're right, that's where the teams target a huge upgrade package. Even more pertinent with a two-day test to come right after the grand prix. You'll see lots of new parts up and down the grid that weekend.
We're into the final three minutes now.
Lots of green flow-viz on the side of Hulkenberg's car. Either that or the Hulk is getting mad again.
Didn't feel right leaving Eric out of the Twitter convo here.
Twenty seconds left in the session and cars are filtering back into the pit lane.
And that's the chequered flag. Raikkonen leads a Ferrari one-two but we didn't see anything really representative from Mercedes today. The world champions seemed perfectly happy to call it a day early after completing its run plan early.
As always, thanks for joining me for this session. We'll be back in two hours to do it all again in FP2, when we'll see the qualifying simulations ahead of the all-important shoot-out in qualifying.