Spanish GP: Fernando Alonso fastest in first practice for Ferrari
Ferrari's Fernando Alonso set the pace in a wet-dry first practice session at the Spanish Grand Prix.
Alonso was 0.203 seconds faster than team-mate Felipe Massa, with Toro Rosso's Jean-Eric Vergne third.
Mercedes' Lewis Hamilton was on a lap that would have been similar to Alonso's fastest before being held up by a Red Bull, ending up sixth fastest.
Sam Michael McLaren sporting director
“We've got lots of new parts - enough for two cars, but we're limited on spares so we'd like to avoid crashing or going into gravel”
The mixed conditions compromised the teams' attempts to assess their latest performance upgrades.
The session started wet and dried progressively throughout, so that drivers were able to use 'slick' dry weather tyres for the final 15 minutes.
Lotus driver Romain Grosjean ended up fourth ahead of Force India's Adrian Sutil and Hamilton.
Williams's Valtteri Bottas was seventh, from Lotus's Kimi Raikkonen, Mercedes' Nico Rosberg and Force India's Paul di Resta.
Apart from an early 'installation' lap, world champion Sebastian Vettel did not run until the track was dry.
He ended up 19th in his Red Bull, after getting tangled up with Hamilton a couple of times, with team-mate Mark Webber 20th.
BBC 5 live analyst and former F1 driver Allan McNish said: "You can't read too much into it because of the conditions but the Ferraris are looking pretty good so far."
BBC F1 technical analyst Gary Anderson said: "We'll get a better idea in the second session if it stays dry but the Ferraris do look quite good. But the Lotus, Mercedes and Red Bull are all competitive."
All the teams have significant upgrade packages on their cars, and much attention was focused on McLaren, who have had an uncompetitive start to the season.
Sporting director Sam Michael said: "We've got lots of new parts on car today and lots of other bits to bolt on and test. Right now, the wet weather doesn't help, but we're still doing some work. We've got enough parts for two cars, but we're limited on spares so we'd like to avoid crashing or going into gravel."
The McLaren has a revised aerodynamic package, with different wing profiles as well as more tightly-packaged bodywork.
1. Fernando Alonso (Spa) Ferrari 1min 25.252secs
2. Felipe Massa (Brz) Ferrari 1:25.455
3. Jean-Eric Vergne (Fra) Toro Rosso 1:25.667
4. Romain Grosjean (Fra) Lotus 1:26.042
5. Adrian Sutil (Ger) Force India 1:26.212
6. Lewis Hamilton (GB) Mercedes 1:26.374
7. Valtteri Bottas (Fin) Williams 1:26.456
8. Kimi Raikkonen (Fin) Lotus 1:26.614
9. Nico Rosberg (Ger) Mercedes 1:26.621
10. Paul di Resta (GB) Force India 1:26.755
11. Daniel Ricciardo (Aus) Toro Rosso 1:26.940
12. Nico Hulkenberg (Ger) Sauber 1:27.061
13. Sergio Perez (Mex) McLaren 1:27.135
14. Esteban Gutierrez (Mex) Sauber 1:27.250
15. Pastor Maldonado (Ven) Williams 1:27.576
16. Heikki Kovalainen (Fin) Caterham 1:28.373
17. Giedo van der Garde (Ned) Caterham 1:28.600
18. Jules Bianchi (Fra) Marussia 1:28.887
19. Sebastian Vettel (Ger) Red Bull 1:29.457
20. Mark Webber (Aus) Red Bull 1:29.473
21. Rodolfo Gonzalez (Ven) Marussia 1:30.314
22. Jenson Button (GB) McLaren no time
Spanish Grand Prix, day one
- Friday, 10 May: Second practice: 13:00 BST live on BBC Two, 12:55 BST on 5 live sports extra, live text commentary online
Spanish Grand Prix, day two
- Saturday, 11 May: Third practice: 09:55 BST live on BBC Two and BBC Radio 5 live sports extra, live text commentary online. Qualifying: 12:10 BST live BBC One, 12:55 BST on 5 live sports extra, live text commentary online.
Spanish Grand Prix, day three
- Sunday, 21 April: Race: 12:10 BST live BBC One and 13:00 on 5 live, live text commentary online. Highlights BBC Three 19:00.