Michael Schumacher has cruised to his fourth consecutive victory after brushing off Jenson Button's challenge at the San Marino Grand Prix.
1 M Schumacher (Ferrari)
2 J Button (BAR)
3 JP Montoya (Williams)
4 F Alonso (Renault)
5 J Trulli (Renault)
6 R Barrichello (Ferrari)
7 R Schumacher (Williams)
8 K Raikkonen (McLaren)
Button led for nine laps after starting the race from pole position, but the Ferrari was much faster and the Englishman had to settle for second.
Juan Pablo Montoya was a distant third for Williams, ahead of the Renaults of Fernando Alonso and Jarno Trulli.
David Coulthard was 13th after damaging his front wing at the first corner.
Coulthard's McLaren team-mate Kimi Raikkonen, who started from the back of the grid following an engine failure in qualifying, scored his first point of the season.
The Finn inherited eight place when Takuma Sato's BAR-Honda retired with engine failure with four laps to go. It was the first time Raikkonen had finished a race in 2004.
Alonso made up three places in the closing stages to grab his fourth place.
The Renault passed both Trulli and Rubens Barrichello's Ferrari with some strong driving around his stop, and then passed Ralf Schumacher in a controversial move on lap 50.
The Spaniard made a late dive inside the Williams at Tosa and the two cars collided, pushing Schumacher into a spin.
Race stewards investigated the incident but decided to take no action.
Alonso said: "He made a little mistake in the corner before. I tried to overtake him, and unfortunately we touched. I think he saw me and closed the door maybe in a bad way."
Alonso then closed the three-second gap to Montoya with three laps still to go, but the Colombian held on to third place.
Like Alonso, Michael Schumacher had used a pit-stop period to gain crucial places.
The German held off a brief challenge from Montoya on the first lap by pushing the Williams on to the grass on the exit of Tosa and then tracked Button for the first nine laps of the race.
Schumacher then completed two record-breaking laps to get himself ahead of the BAR by the time he came out from his first pit stop.
Schumacher never looked back, and had moved into a half-minute lead before easing off in the closing laps to win by 9.7 seconds.
"At the start it was mind-blowing what Jenson put up in
front - I thought it was raining for me and dry for him! He was disappearing and it took a few laps to get everything going and chase him," Schumacher said.
"His first stint was very quick and I was thinking it would be a busy and tough afternoon but for whatever reason we kept our pace throughout the race and they dropped off."
Button was the only man able to put Schumacher under any pressure - Montoya finished a further 11.9secs adrift.
That gap flattered the Williams because Button was told to ease off in the closing laps following Sato's retirement.
"The first lap was a fantastic feeling, I was really wringing the neck of the car and wanted to build a gap," Button said.
"My pace in the first stint I was quite happy with. After that I struggled a bit compared to Michael.
"The wind changed direction and the car was a bit nervous, but even with those problems the pace was still good."