In heat so brutal that even the pigeons were reluctant to venture outside, the Italian cyclist Paolo Bettini yesterday defied some mean Athens streets and a succession of gung-ho, pace-setting opponents to win a gruelling men's road race in a ding-dong finale.

During an afternoon of spills, big-name retirements and strategies straight from the madhouse, Bettini took gold in five hours, 41 minutes and 44 seconds, pipping Portugal's Sergio Paulinho into second by a hundredth of a second. Belgium's Axel Merckx, the son of the five-times Tour de France winner Eddy, took bronze. Germany's Jan Ullrich, the defending Olympic champion, finished in the chasing pack.

"After such a tough race, I was concerned about losing out at the end, especially with Paulinho putting me under pressure" said Bettini, a 30-year-old from Cecina. He finished 11th in this year's Tour de France and has amassed 25 top-10 finishes in major races since finishing ninth at the Sydney Olympics but recently lost two World Cup races by the narrowest of margins at the death. "But this feels wonderful, as victory not just for me but my fellow Italian riders."

The mercury was nudging 100 degrees at midday, 45 minutes before the start of the race, a 139-mile history lesson in 17 laps of the Greek capital. The route took in the National Archaeological Museum, Mount Lycabettus (the highest point in the city), The Vouli (parliament building) and a cluster of ancient sights. Yet as early as first lap the talking point was not so much Acropolis as a cropper.

Spain's Igor Astarloa, the world champion, retired within 10 minutes after a crash that saw him briefly hospitalised. Dutchman Michael Boogerd was among others who crashed out or retired exhausted. Some riders lost up to 7lb in weight, and that despite drinking 10 litres of water on the way round.

In such conditions, it was reckless for Magnus Backstedt, a 6ft 4in 15st Swede, to launch a solo breakaway on the second lap and storm into a three-minute lead. France's Richard Virenque, the King of the Mountains for a seventh time in the Tour de France, caught him, as did Hungary's Lazlo Bodrogi. But all three had pushed too hard by the 10th lap. Backstadt dropped out, and, under attack from a German contingent including Andreas Kloden, Virenque and Bodrogi, fell through the field. Yet Kloden, the bronze medallist in Sydney and second to Lance Armstrong in the Tour de France, had also overstretched himself. He retired.

Bettini and Paulino made their moves in the final laps. As Bettini crossed the finish line the roar was loud enough briefly to unsettle a gathering of some 500 pigeons still taking refuge from the sun under one of the temporary seating stands. Earlier, when a local fancier had thrown them a bag of grain, they had fought beak and claw in a seething mass for their share of the spoils. It was that kind of day, even in the shade.