The Colombian started third on the grid and thus did mightily well to come home ahead of both team-mate Ralf Schumacher and McLaren's Kimi Raikkonen, who started ahead of him.

Montoya disposed of the Finn when the McLaren got bogged down at the start, then hounded Ralf up to the first of their two pit stops. Both Williams drivers pitted early, suggesting that they had started the race relatively light on fuel and explaining why they and Raikkonen had been able to run away from the group behind.

Indeed, there was much talk of the Ferraris, in particular, having started fuel heavy. Jarno Trulli ran the first stint in fourth place, keeping his Renault ahead of Michael Schumacher's Ferrari. The Italian almost got past Montoya off the line, before being squeezed back to fourth by Raikkonen as the field approached Ste Devote.

However, the order changed dramatically at the first stops, as Ralf was a little slow on his in-lap, his car sliding all over the place at the Grand Hotel hairpin as Montoya locked onto his rear wing. Then the Colombian put in a lap faster even than Ralf's pole position lap which meant he re-emerged ahead of Ralf, regaining the effective lead of their fight, albeit now down in seventh place.

Both Williams and McLaren were concerned, though, as the Ferraris continued to circulate. There had even been talk in the paddock that Ross Brawn might be attempting something very brave with his drivers' race strategy, perhaps even sending them out with enough fuel to need to pit only once.

However, when Barrichello and then Michael pitted, it became apparent that this wasn't the case, as they didn't take on sufficient fuel. So, Williams and McLaren had reason to smile, except for the fact that the race after the first round of stops was to be a two-horse race between Montoya and Raikkonen, Ralf faded somewhat in his second stint with balance problems.

Amid all this, Michael had made it up to third place, getting past Trulli courtesy of his longer first stint. The order was to change little through to the end of the race, with Michael gradually able to haul himself up behind the leading duo, but never troubling them. And so it was that Montoya controlled proceedings, able to keep his Williams in front on this circuit on which overtaking is so difficult. The result will have gone a long way towards cementing the future between Williams and engine supplier BMW.

Ralf lost further ground to finish fourth, a disappointing result considering that he'd started from pole. Fifth place went not to Trulli nor Coulthard - who was never more than a second or so off his tail - but to Alonso who avoided traffic and put in some very quick laps before his second pit stop to emerge in front and then stay there to the finish. The final point went to Barrichello who had a tidy middle part of the race but never really troubled those in front of him.

Nobody was happier afterwards than Montoya and his Williams crew. "Everybody in the team needed this," he enthused. "Ralf got pole and I got the win. It was awesome. The team told me that I had to get a move on to keep Kimi behind me after his second stop, but I managed this and then I was able to slow down and control the race."

Raikkonen, who has often looked somewhat sulky when finishing second was happier this time. "I don't seem to be very lucky when I start from second place on the grid," he commented. "After Juan Pablo got ahead of me at the start, my race was spent following him. I did have a chance to maybe get past him, but this was spoiled by hitting traffic before each pit stop. And, as everyone knows, you have no chance of passing someone at Monaco unless they make a mistake."

Having failed to make it three wins in three starts in the new Ferrari F2003-GA, and indeed to achieve his stated ambition of equalling the late Ayrton Senna's six wins at Monaco, Michael Schumacher was not surprisingly less than ecstatic with the way that his weekend had gone. "If I hadn't been stuck behind Trulli in the first part of the race, I might have had a chance of keeping Raikkonen in sight," said the five-time World Champion. "I even took on more fuel so that I could have a longer second stint, but that didn't work either. So, I suppose third place from fifth is alright."

So, Raikkonen has extended his lead at the top of the drivers' championship table to four points over Michael Schumacher, while his McLaren team has moved back in front of Ferrari by two.