Monza: Lewis Hamilton revived his bid for this year's Formula One world title on Sunday when he swept to a dominant triumph for McLaren to record his first ever win in the Italian Grand Prix.
The 27-year-old Briton, starting from pole position, led throughout apart from a brief spell during the mid-race pit-stops to claim his third win this year and the 20th of his career.
It lifted him back into contention for the championship, but his McLaren team-mate and fellow-Briton Jenson Button's hopes of a second world title disappeared as he was forced to retire with 20 laps remaining.
"This is amazing for me and I thank my team for doing an incredible job," said Hamilton. "It is a great day for everyone."
Alonso now leads the championship with 179 points ahead of Hamilton on 142 and Finland's former world champion Kimi Raikkonen on 141 with defending champion Sebastian Vettel on 140 with seven races remaining.
Button's demise allowed Mexican Sergio Perez of Sauber to gain full reward for a dazzling drive by finishing second 4.3 seconds behind Hamilton, but 16.2 ahead of championship leader Spaniard Fernando Alonso of Ferrari, with Brazilian Felipe Massa fourth also in a Ferrari.
It was Perez's third podium finish of the season and endorsed the view of many paddock observers that he could be on the move to replace Massa at Ferrari next year.
Raikkonen finished fifth for Lotus ahead of Michael Schumacher of Mercedes, the 43-year-old seven-time champion, with countryman Nico Rosberg seventh in the second Mercedes.
Briton Paul Di Resta came home eighth for Force India ahead of Japanese Kamui Kobayashi in the second Sauber and Brazilian Bruno Senna, who capitalised on the late retirement of Australian Mark Webber of Red Bull, took the final point for Williams.
Vettel struggled through a disappointing race during which he forced Alonso off the track, was handed a drive-through penalty and finally retired his Red Bull due to technical problems.
Hamilton dominated from the start steering his McLaren clear of the field while Massa 20 metres behind him, used the leader's tow to pull clear and pass Button before the chicane.
After one rebutted effort to pass Hamilton for the lead, Massa defended an attack from Button on approach to the second chicane. Behind them, Alonso moved swiftly from 10th to seventh.
In an intriguing early battle between Germany's two greatest drivers, Schumacher held fourth and resisted Vettel until lap four when the champion dived past him at the first chicane.
All this left Hamilton in command, leading Massa by more than four seconds by lap 15 when the pit stops began, Button, third, was a further 1.3 seconds adrift and Vettel, fourth, another 1.7 away with Alonso chasing him down.
Vettel's chances of winning disappeared when he was handed a drive-through penalty for his belligerent aggression, a punishment he took on lap 34, one lap after the luckless Button was forced to retire from second.
Button's demise lifted Massa to second ahead of Alonso with Perez flying on fresh tyres as the second stops began.
On lap 37, Massa was told to 'think about your tyres... Fernando is behind.' It was a coded message and, on lap 40, Alonso coasted by on the straight to take second.
Perez then swept around the outside of Massa to set up a dramatic finale with nine laps remaining and a little later moved up to second with another sensational move, on Alonso but was unable to trouble Hamilton.