Belgian Grand Prix
Venue: Spa-Francorchamps circuit Qualifying: Saturday 6 September at 1300 BST Race: Sunday 7 September at 1300 BST Coverage: Live coverage on ITV, live text commentary on the BBC Sport website and live commentary on BBC Radio 5 Live streamed on the BBC Sport website
Massa is six points adrift of Hamilton in the drivers' standings
Felipe Massa and Fernando Alonso topped the timesheets in Friday's dual practice sessions ahead of the Belgian Grand Prix in Spa.
Massa confirmed Ferrari's dominance in Spa with a lap of one minute 47.284 seconds - the fastest of the day.
But it was Renault's Alonso who topped the timesheets in 1:48.454 in a rain-interrupted second practice, which was stopped when Giancarlo Fisichella spun.
McLaren's Lewis Hamilton finished third in the first session and then fourth.
Massa is six points behind Hamilton in the drivers' standings and is looking to close the gap by building on his victory in Valencia two weeks ago.
The Brazilian was in a class of his own in the first practice session; knocking out fastest lap after fastest lap in the closing stages as team-mate Kimi Raikkonen and Hamilton were unable to close him down.
After a spell of testing in Monza, Ferrari believe they have ironed out their technical problems and are ready to launch a renewed attack on the drivers' title.
Ferrari's defending world champion Raikkonen is hoping to use his experience at Spa, where he has won the last three Grands Prix, to propel himself back into the title race.
But the Finn's run of bad luck continued in the second session, when he spun, slid into a tyre wall and dislodged his rear wing.
He finished fifth overall to follow up his second place in first practice.
Soon afterwards, Fisichella spun coming out of a patch of standing water and crashed into a metal barrier before bringing his Force India to a halt on the grass.
We're going for the win - we're just as competitive as Ferrari
The session was then halted for 10 minutes to remove Fisichella's car while officials brushed away the water.
Australian Mark Webber was also caught out by a shower in the second session as he slid into the barriers at Rivage, while Renault's Nelson Piquet also lost his rear wing.
Alonso looked to be taking advantage of a lighter fuel load as he finished top of the timesheets, just 0.050 secs ahead of Massa.
The McLarens of Heikki Kovalainen and Hamilton followed the Brazilian home in a reversal of their placings from first practice.
Nonetheless, Hamilton remains confident that he can challenge the Ferraris for a race victory on Sunday in wet or dry conditions.
"This track is a great challenge in the dry, but in the wet it will be so tricky for everyone," the 23-year-old said.
"We're going for the win. We're just as competitive as them. We're pretty much equal with them.
"They have a bit more speed at the end of the straight, but I don't think it will make any difference.
Alonso was the surprise pacesetter for Renault in second practice
Overall, six drivers - Massa, Raikkonen, Hamilton, Kovalainen, Alonso and Webber - set quicker times in the morning run than Alonso in the afternoon.
The two sessions, one played out in overcast, chilly conditions and the other affected by sudden rain, proved just how changeable the conditions in Spa can be and underlined their importance in determining the outcome of Sunday's race.
The drivers return to the winding track through the Ardennes Forest for final practice and then qualifying at 1300 BST on Saturday.
First free practice session times for the Belgian Grand Prix:
1. Felipe Massa (Brz) Ferrari 1 min 47.284 secs
2. Kimi Raikkonen (Fin) Ferrari 1:47.623
3. Lewis Hamilton (GB) McLaren-Mercedes 1:47.878
4. Heikki Kovalainen (Fin) McLaren-Mercedes 1:47.932
5. Fernando Alonso (Spn) Renault 1:48.104
6. Mark Webber (Aus) Red Bull-Renault 1:48.428
7. Sebastien Bourdais (Fra) Toro Rosso-Ferrari 1:48.557
8. Sebastian Vettel (Ger) Toro Rosso-Ferrari 1:48.958
9. Timo Glock (Ger) Toyota 1:48.997
10. Nelson Piquet (Brz) Renault 1:49.068
11. Robert Kubica (Pol) BMW Sauber 1:49.139
12. Nick Heidfeld (Ger) BMW Sauber 1:49.185
13. Nico Rosberg (Ger) Williams-Toyota 1:49.611
14. Jarno Trulli (Ita) Toyota 1:49.625
15. David Coulthard (GB) Red Bull-Renault 1:49.849
16. Giancarlo Fisichella (Ita) Force India-Ferrari 1:49.986
17. Adrian Sutil (Ger) Force India-Ferrari 1:50.117
18. Kazuki Nakajima (Jpn) Williams-Toyota 1:50.125
19. Jenson Button (GB) Honda 1:50.464
20. Rubens Barrichello (Brz) Honda 1:50.905
Second free practice session times for the Belgian Grand Prix:
1. Fernando Alonso (Spn) Renault 1 min 48.454 secs
2. Felipe Massa (Brz) Ferrari 1:48.504
3. Heikki Kovalainen (Fin) McLaren-Mercedes 1:48.740
4. Lewis Hamilton (GB) McLaren-Mercedes 1:48.805
5. Kimi Raikkonen (Fin) Ferrari 1:49.328
6. Nico Rosberg (Ger) Williams-Toyota 1:49.405
7. Sebastian Vettel (Ger) Toro Rosso-Ferrari 1:49.427
8. Adrian Sutil (Ger) Force India-Ferrari 1:49.585
9. Jarno Trulli (Ita) Toyota 1:49.715
10. Nick Heidfeld (Ger) BMW Sauber 1:49.725
11. Robert Kubica (Poland) BMW Sauber 1:49.875
12. David Coulthard (GB) Red Bull-Renault 1:49.922
13. Sebastien Bourdais (Fra) Toro Rosso-Ferrari 1:49.948
14. Timo Glock (Ger) Toyota 1:50.281
15. Kazuki Nakajima (Jpn) Williams-Toyota 1:50.364
16. Giancarlo Fisichella (Ita) Force India-Ferrari 1:50.740
17. Jenson Button (GB) Honda 1:50.925
18. Rubens Barrichello (Brz) Honda 1:51.238
19. Nelson Piquet (Brz) Renault 1:51.334
20. Mark Webber (Aus) Red Bull-Renault 1:51.640