After crashing out at the first corner of last Sunday’s Belgian Grand Prix along with championship leader Fernando Alonso, and amid the saga of his contract negotiations with McLaren, Hamilton conjured a superb drive at Monza to claim his third win of the season and 20th of his career.
The Briton finished 4.3 seconds ahead of Sauber’s Sergio Perez in second place, with Alonso giving the Ferrari fans plenty to cheer with third to establish a 37-point gap in the standings ahead of new second-placed man Hamilton.
Felipe Massa came fourth ahead of Kimi Raikkonen and Michael Schumacher.
McLaren’s Jenson Button and Red Bull’s Sebastian Vettel both retired.
Vettel’s retirement, with his second alternator failure of the weekend, means that he drops to fourth, two points behind Hamilton and one behind Lotus’s Raikkonen.
If Vettel’s retirement was bad enough for Red Bull, worse followed in the closing stages when team-mate Mark Webber dropped three places from seventh to 10th with a spin on to the grass, only to retire in the pits a lap from home.
A happy Hamilton said: “It’s a fantastic win in front of the best crowd. I’m happy for the team. It’s been the best day.”
Taking the bulk of the cheers from the crowd, Alonso was content enough with third as he said: “It was a difficult race starting 10th, but we knew we had the quickest car, so to recover the way we did was good.”