Welcome to live coverage of free practice 3 from the Spanish GP at Montmelo!

Right then, that's FP3 - each of the sessions topped by a different car (Ferrari, Mercedes, Re Bull) and it will be anybody's game in qualifying. Join us LIVE for that at 13:00 UK time!

P1 for Sebastian Vettel 1:23.168, and there;s the chequered flag.

Some quick times late on here, and it's Pastor Maldonado who comes out on top with a 1:23.336, the fastest lap of the weekend so far!

Lewis Hamilton runs into trouble late on a fast lap. Kimi Raikkonen and an HRT - Karthikeyan - get in the Brit's way. He was on pace for P1, but that hold-up cost him two seconds. Still, it's only practice.

P4 on softs for Jenson Button - 1:23.909.

Ferrari engines 1-2-3 - Perez (Sauber), Alonso (Ferrari), Vergne (Toro Rosso).

OK, that was a false alarm - Vettel is back. His problem has been fixed, and it may well be he was just going for a pee. Fair enough.

P2 for Fernando Alonso, who is less than a tenth of a second off the pace. He will be desperate to perform in front of a home crowd.

Seb Vettel has left the pits, and it would appear he will not be back this hour. A minor setback for the world champion.

Helmet on for Romain Grosjean - he may well be heading back out before the end of the hour.

Problems for Sebastian Vettel. While Mark Webber tears round on soft tyres, Vettel is in the pits with half a dozen mechanics standing over the cockpit of his car. He evidently has a problem.

Just to remind you, tyre compounds are indicated by the colour of the writing on the sidewalls. It's white for medium, yellow for soft and red for super-soft.

Soft tyres starting to come out, and Sergio Perez clocks a 1:23.7.

Felipe Massa runs wide, and Jenson Button has a whinge over the radio about a lack of grip. Meanwhile, Nico Rosberg goes P1.

Kimi Raikkonen has been having a moan about understeer to the Lotus team. He's down in P10.

And on the subject of pitstops, here is an excellent article by Will Gray on the fancy whizz-bang technology being employed these days.

Lewis Hamilton comes into the pits for a change of steering wheel - apparently just a practice run. McLaren have had their share of pitstop woes this season, of course.

Tyre fans may be interested to know that nobody has yet employed soft rubber so far today.

Nice onboard shot with Toro Rosso's Jean-Eric Vergne, who absolutely flings his car into the pitlane. It's terrifying - and impressive - stuff.

It's a very quiet session - just five drivers on the track. One of them is Pastor Maldonado, who goes P2 with a 1:24.571.