One more heavy downpour was all that kept Lewis Hamilton from denying Sebastian Vettel the best day of his life.

The baby-faced German eclipsed the previous record set by Fernando Alonso at the 2003 Hungarian Grand Prix by just over 10 months.

But it could have been a far different story if the rain that led to a rare start behind the safety car had again hit Monza midway through the race.

And after a gamble that backfired in qualifying on Saturday, Hamilton shied away from another bold move that would also have yielded the win.

There can be no doubt this will go down as Vettel's day, but it was the brilliance of Hamilton that lit up the race early on.

Starting from a career-low 15th on the grid after making the wrong tyre call in the second qualifying period, in atrocious conditions Hamilton slowly scythed his way through the field.

David Coulthard, Giancarlo Fisichella, reigning world champion Kimi Raikkonen, Nick Heidfeld, Timo Glock, Robert Kubica, Alonso, Jarno Trulli and Nico Rosberg were all picked off inside 24 laps.

It was breathtaking, exhilarating stuff, and when McLaren team-mate Heikki Kovalainen, Mark Webber and Felipe Massa all pitted, Hamilton was running second.

On a wet track, but not saturated, Hamilton made what he believed would be his only stop on lap 27, remaining on extreme tyres as had every other driver before him as the call was for more rain.

But over the next few laps Heidfeld, Alonso and Kubica - also on one-stop strategies - all opted for the intermediates, and it was the correct call as they finished fifth, fourth and third.

If the rain forecast had arrived at that stage, Hamilton would have been odds on for the win as it is certain he would have reeled in the immaculate Vettel who drove faultlessly.

Instead, Hamilton was forced to switch to the intermediates on lap 36, finishing seventh, a place behind his main championship rival in Ferrari's Massa, with the 23-year-old's lead now a single point.

"I got up to second at one stage, so it's a shame I had to stop again because I didn't need more fuel, it was just down to track conditions," said Hamilton.

"If it had kept on raining I feel pretty confident I probably could have won from even 15th on the grid.

"But then when I changed tyres, perhaps today I needed the gamble I took yesterday."

Asked whether he felt frustrated, Hamilton added: "Not really. It's just something you have to deal with.

"I showed I was quickest in the wet, showed that I had great pace, and I think a win was possible.

"But as a drive, it's probably right up there. Driving through the pack, passing and leaving someone behind like Kimi, it was a great feeling."

As yesterday, McLaren's weather forecasters called it wrong, and on this occasion Hamilton heeded their advice rather than making the call on his own.

But given Massa could only finish in the position he started, that underlines Hamilton's achievement, in particular as Raikkonen only managed ninth from 14th.

"With me being right at the back, they (Massa and Raikkonen) both missed an opportunity to take lots of points off me," assessed Hamilton.

"The other way round, if I'd been in Q3 and Massa had been out of the top 10 we would have got a lot more points than them, so it's not that bad."

As Hamilton conceded, it was "damage limitation" at the end of the day, and now he goes into the final four races with the slimmest of margins, pending next Monday's appeal into 'Spa-gate'.

"I'm relieved to still be leading," added Hamilton.

"But then I'm not surprised because I drove my backside off, and you all know what I can do in the wet.

"I had no doubts in my mind I could do a good job, catch up and win. I thought it was possible."

Instead, the victory went to Vettel a day after clinching his debut pole, with yesterday's celebrations inside Toro Rosso paling into comparison by what transpired today.

"This is the best day of my life," said an emotional Vettel.

"It is better than I ever expected. I couldn't believe it when I kept seeing 'P1' on my board, but I kept my focus and kept pushing.

"It has been a perfect weekend."

Kovalainen finished as runner-up to help McLaren close the gap to Ferrari in the constructors' championship to just five points.

Webber claimed the final point in his Red Bull, whilst Jenson Button was 15th for Honda, and Red Bull's David Coulthard 16th.