Button, on the front row for the second successive race, had conceded beforehand he was worried by the power of the Renaults who formed the second row directly behind him.

His fears were founded as Alonso passed him, and although he managed to fend off team-mate Giancarlo Fisichella, he was down to fourth as Michael Schumacher had also managed to force his way past the Briton.

Raikkonen's McLaren team-mate Juan Pablo Montoya, starting at the back of grid after his shunt in qualifying, produced a storming first lap as he was up to 11th by its end.

The Colombian managed to avoid a number of minor incidents that unfolded through the first corners of the 4.574km circuit, one of which saw Takuma Sato catch Fisichella.

Like Sato, Jarno Trulli and Mark Webber were also forced into the pits at the end of the first lap, with the latter apparently retiring with a broken suspension on his Williams.

But while the drama unfolded, with the Sauber of Jacques Villeneuve and Minardi of debutant Robert Doornbos also colliding on lap four, Raikkonen was away and clear.

At the end of the first 10 laps of the 67-lap race, the Finn was 3.8 seconds clear of the chasing Alonso, followed by Schumacher and Button, with Nick Heidfeld in the second Williams and Red Bull Racing’s David Coulthard completing the top six.

Perhaps the only hope for the field of stopping Raikkonen was rain as a sharp shower had hit the circuit 45 minutes before the start, with the prospect of more to follow.

Raikkonen was eking out his lead over Alonso which had grown to just over six seconds by the end of lap 15 on which Heidfeld was the first of the leading protagonists into the pits, with the German out again in eight seconds.

The leading duo were comfortably dropping Schumacher, a former three-times winner at this track, who was more than 10 seconds down on Alonso after 20 laps.

Button was at least in relatively close attendance as the 25-year-old was less than three seconds adrift of the German before he pitted at the end of the 20th lap, clocking a time of 9.2 seconds.

Alonso and Schumacher came in two laps later, with both out again in 9.3 seconds, that coming moments before the second Red Bull of Christian Klien took an uncomfortable ride across the gravel.

It was on lap 23 that Doornbos came in for a 10-second stop-go penalty, seemingly for his earlier shunt that forced Villeneuve off the track and led to an investigation by the race stewards who quickly found the Dutchman guilty of poor driving.

By lap 25, Raikkonen was in for his first stop which took nine seconds to complete, and such was the earlier advantage he had amassed, he emerged comfortably clear of Alonso.

The big mover was Montoya who was up to third when he was the last of the drivers in to take his first pit stop, and by the end of lap 30 he was running fifth behind Raikkonen, Alonso, Schumacher and Button.

Unfortunately for Villeneuve, he was involved in another accident, this time with the Jordan of Narain Karthikeyan as the Indian moved over to block an overtaking manoeuvre.

With the Canadian nowhere to go, he ran into the back of Karthikeyan, removing his nose cone and forcing him into another pit stop.