Raikkonen quickest in practice 1 - Bahrain

The Finn was the first of the leading contenders to take to the track, emerging from the Ferrari garage after half an hour and immediately moving to the top of the standings by 1.2 seconds.

Raikkonen then improved by half a second on his next lap and his 1:33.162 proved impossible to beat.

Massa did not attempt a flying lap until nearly an hour into the session, and his first effort was a second shy of Raikkonen's, although he improved to within 0.517 seconds later in his run.

McLaren seemed hard-pressed to match Ferrari's pace, both Fernando Alonso and Lewis Hamilton lapping 1.5 seconds slower than Raikkonen at first.

They closed the gap to 0.9 seconds on their final runs, but both appeared to be struggling for grip all morning.

Alonso went off the road at Turn 10 on two consecutive laps and also drifted onto the sand at Turn 11, while Hamilton had two moments at the final corner.

They weren't the only drivers battling to stay on the road after overnight storms rendered the track very 'green'.

Heikki Kovalainen went straight on at Turn 1 early in the session, Alex Wurz had a spin at Turn 7, Massa had to save a wild moment after getting onto the kerbs at Turn 7, and Scott Speed, Giancarlo Fisichella and Christijan Albers also had minor incidents.

The Toyotas had set the pace before the top two teams appeared, and Jarno Trulli's early time remained sufficient for fifth place, ahead of BMW's Nick Heidfeld and Robert Kubica.

Vitantonio Liuzzi jumped to a surprise eighth position in the final seconds of the session. His improvement, and similar late gains by the two Williams, knocked Jenson Button out of the top ten after he had earlier put the Honda as high as seventh.

But while Toro Rosso broke into the top eight, it was a disappointing morning for Red Bull, with David Coulthard and Mark Webber ending the session slower than all bar the Spykers.

For the first time this season, only regular race drivers participated in Friday morning practice. BMW's test driver Sebastian Vettel has a clashing World Series by Renault event at Monza this weekend, while Williams' Kazuki Nakajima is focusing on his GP2 debut in Bahrain.

Pos  Driver        Team                    Time              Laps
 1.  Raikkonen     Ferrari            (B)  1:33.162           21
 2.  Massa         Ferrari            (B)  1:33.679 + 0.517   17
 3.  Hamilton      McLaren-Mercedes   (B)  1:34.110 + 0.948   17
 4.  Alonso        McLaren-Mercedes   (B)  1:34.161 + 0.999   15
 5.  Trulli        Toyota             (B)  1:34.896 + 1.734   26
 6.  Heidfeld      BMW Sauber         (B)  1:35.076 + 1.914   30
 7.  Kubica        BMW Sauber         (B)  1:35.248 + 2.086   24
 8.  Liuzzi        Toro Rosso-Ferrari (B)  1:35.292 + 2.130   23
 9.  Rosberg       Williams-Toyota    (B)  1:35.375 + 2.213   19
10.  Wurz          Williams-Toyota    (B)  1:35.398 + 2.236   20
11.  Button        Honda              (B)  1:35.445 + 2.283   24
12.  Kovalainen    Renault            (B)  1:35.474 + 2.312   21
13.  R.Schumacher  Toyota             (B)  1:35.573 + 2.411   24
14.  Fisichella    Renault            (B)  1:35.697 + 2.535   17
15.  Speed         Toro Rosso-Ferrari (B)  1:35.726 + 2.564   22
16.  Sato          Super Aguri-Honda  (B)  1:35.856 + 2.694   15
17.  Barrichello   Honda              (B)  1:35.911 + 2.749   20
18.  Davidson      Super Aguri-Honda  (B)  1:36.243 + 3.081    6
19.  Webber        Red Bull-Renault   (B)  1:36.483 + 3.321   18
20.  Coulthard     Red Bull-Renault   (B)  1:36.513 + 3.351    7
21.  Sutil         Spyker-Ferrari     (B)  1:37.084 + 3.922   27
22.  Albers        Spyker-Ferrari     (B)  1:38.258 + 5.096   29

All timing unofficial