Raikkonen is out on the medium compound.
Raikkonen goes P2 with his first timed lap on the mediums.
Vettel does better than his team-mate, going purple through the first and final sector to move into P1 with a 1:28.673.
The times will continue to drop as the track continues to dry.
Ericsson moves into third.
@Leonardo: Well, you would expect at some point in the next few races they will get their hands on the Mercedes power unit upgrade, and clearly they are maximising the potential of the B-spec car now.
Raikkonen goes into P1, a 1:28.490.
@Shirish: Spoke too soon ;) The track is getting drier so shouldn't read too much into the early times as of yet.
Ericsson has briefly split the Ferraris in P2 as Merhi has a lock up into Turn 1 and runs over the 'sleeping policemen' kerbs.
@Leonardo: Absolutely, he brings an awful lot of money with him.
The Ferrari drivers exchanging times at the top of the timing screen as Vettel re-claims top spot with a 1:26.537.
Rosberg being told to exercise caution on the kerbs as they are still wet.
Vettel getting quicker and quicker out there, lowering the benchmark down to 1:25.799. He's 1.7s quicker than anyone so far but Rosberg has just started his first timed lap on the medium tyre.
Rosberg going incredibly slowly, but looks like he's backing off rather than struggling with an issue. He didn't move that far off the racing line then but he seems to be back up to speed now.
Replays showing Merhi having a heavy lockup into the Roggia as he came past Rosberg.
We have yellow flags and Ricciardo has stopped at the Roggia. They are wheeling him off the escape road.
@AhmedFaraz: Yep, that's always been the plan for at least one of the announcements.
@lo: With such limited movement around the grid next year it's hard to see where he could get a race seat.
"Every time I hit the brakes I'm locking fronts," Button complains.
Bottas has moved into second, three tenths off Vettel. Raikkonen is in third, 1.2s off his team-mate.
Massa climbs above his team-mate but is still a tenth shy of Vettel's headline time. Williams showing its usual Saturday improvement.
As you were. Rosberg's first timed lap on the mediums moves him into P1, shaving three tenths off Vettel's best to cross in 1:25.480.
Hamilton is out on track too.
Button has pulled his McLaren into the dizzy heights of 11th. Alonso just behind in 12th.
@Rawpace: No sign of them yet aside from two early exploratory laps.
@ramniwassingh: They did, but you have to add Williams into the equation today as we never see the best from them on Fridays. Certainly Force India will fancy its chances of battling in the top six.
Hulkenberg leading the two Williams drivers through the speed trap times currently.
@zhrazor: It's not unusual for him to have spoken to teams on the grid as this tends to happen in the middle of the season. The only logical place I can see him or Vandoorne ending up next year (if McLaren retains Button) is at Manor, but then it has a partnership with Ferrari and not Honda. That's certainly one to keep an eye on in the next couple of weeks and months.
Hamilton's first time on the mediums is only good enough for fifth but he's on a much quicker lap this time around.
@lo: Mediums all around so far, but expect to see some softs later.
Hamilton had gone purple through the first two sectors but did not complete the lap, instead deciding to return to the pits.
Replays show Button sliding through Turn 1.