Raikkonen went 1.1s quicker but that time should keep improving.
Hamilton goes first, with a two-second improvement on the soft tyre on just his first lap. The new benchmark a 1:38.726. Those tyres should keep getting quicker as well.
@Ron: You heard it here first....
Hamilton's benchmark the quickest of the weekend so far, by the way. Rosberg hasn't managed to improve yet so not sure what's the issue there.
Rosberg not looking as comfortable as Hamilton on his soft tyre runs at the moment, he crosses third - 0.960s behind Hamilton, who has just gone purple in the first sector.
@Michael: Belgium certainly has had an impact on him. I also wonder how its sits with him that he's converted so few pole positions into victories this year, that has to weigh on the mind.
Well, as I say that, Hamilton has a big spin at the penultimate corner at the end of another very, very quick lap. His tyres are incredibly shot after that and he pulls across the track and into the pits.
The final two corners look incredibly tricky. That a good example of Hamilton pushing the limits of the track in this session. He seems to be enjoying himself. It seems his car just stepped out when he touched the brake pedal.
Rosberg can't improve on third, he's still nearly a second down on Hamilton. I wonder if he's still on that creative set-up?
@Kristiyan: Well at the moment you would think so, but let's not forget Mercedes seems to turn the quick up themselves in qualifying. At the moment I think Hamilton looks nailed on for pole BUT we've said that before this season and been proved wrong. On FP2 and FP3 pace, Hamilton is in his own little element on the soft tyre.
Less than three minutes left of this session.
@Parth: They seem to hold up for three or four laps - Hamilton was on his fourth lap and still pushing and setting purple sectors. It seems to be in the first sector where the lap improvements seem to be coming.
Let's hope Marussia can get out for qualifying.
@nalakag: He may have to explain himself to the stewards but, in all honesty, I don't see what else he could do.
Bottas reduces Hamilton's advantage to 0.371s.
Rosberg getting faster and faster and now improves to 0.290s behind Hamilton. He crosses with 20 seconds left of the session so one more lap left.
Remarkably, that's Rosberg after eight laps on the soft tyres, suggesting Hamilton is turning those tyres on a bit quicker.
@MarkWebber: This is one point I've made time and time again this season, Ricciardo's starts are his real Achilles Heel. I don't remember a race where he had a clean getaway and didn't get passed into Turn 1.
Vettel improves to P10 as the clock expires.
Button down in 11th, then, so McLaren in a very contrasting situation to yesterday.
@abhishek: He certainly isn't happy with the feeling of his car currently. Fascinated to see whether he can get on top of that for qualifying.
Anyway, that's all from this final session as the cars filter back to the pit lane.
Thanks as ever for joining me today and please be sure to join us again for qualifying in just under two hours time.
Some fascinating questions to be answered this afternoon in qualifying - please be sure to join us again for that!