Swiss rider Johann Tschopp won the 20th and penultimate stage of the Tour of Italy from Bormio to here on Saturday as Italian Ivan Basso held onto the leader's pink jersey.
Australian world road race champion Cadel Evans took second on the mountain top finish after 178km of racing with Basso third as he extended his lead in the overall standings to Spaniard David Arroyo.
While Basso's hold on the pink jersey never looked in doubt, the real race seemed to be on for the minor placings.
Tschopp had made a break with Italian veteran Gilberto Simoni from a dangerous-looking lead group on the penultimate climb, the gruelling Gavia.
He dropped Simone on the descent and then made the solo bid on the Passo del Tonale.
"This is extraordinary, I have a feeling I'm dreaming. I'm really happy. I'm on another planet," he enthused. "I wouldn't have given away the chance to be first at the top of the Gavia because it was the Cima Coppi (the highest peak of the race), then it put me in a situation of winning. It's fantastic."
The day had started with a remarkable break on the first of five climbs that included former Tour de France winner Carlos Sastre and Kazakh Alexander Vinokourov, sixth and eighth respectively in the standings.
It was a long and brave bid to make an impact on the standings and Basso's Liquigas team was alive to the threat and never let their lead creep over the two minute mark. But that early push ensured the pink jersey group was whittled down to about 40 riders with half the race still to come.
Tschopp's bid was for the stage victory and Vinokourov attacked his fellow chasers on the Tonale to try to catch the Swiss rider but he was followed by Italian Daniele Righi.
Sastre had dropped back and on the final climb he was caught by the Liquigas-led group.
But the real drama came when Evans launched a devastating attack with 3km left. No one reacted initially and Evans flew up the road before blowing past Vinokourov and Righi and going after Tschopp.
Evans started the day fifth in the standings at 4min down and fourth-placed Michele Scarponi finally reacted when he realised his position might come under threat. His acceleration decimated the Liquigas-led group and only Basso could hold his wheel.
Second-placed Arroyo was dropped but grimly hung on in there to limit his losses.
Evans came over the line 16sec behind Tschopp and picked up 12 bonus seconds with Basso picking up eight bonus seconds as he arrived 24sec down on the winner.
Arroyo limited his losses as he came home 40sec after Tschopp to hold onto second overall.
Basso now leads Arroyo by 1:15 with the Italian's team-mate and compatriot Vincenzo Nibali third at 2:56, just a second ahead of Scarponi.
Basso paid tribute to his team-mates Alessandro Vanotti and Nibali for helping him stay in pink.
"This is another positive day, we controlled it. Vanotti has done an exceptional job. Everybody knew that Vincenzo Nibali is a champion. A part of this jersey is his."
Evans is still fifth but with a 51sec deficit to Nibali he could realistically hope to pull that back in Sunday's 15km time-trial around Verona an earn a place on the podium.
Basso, normally a better time-trialer than Arroyo, looks set for his second Giro title, four years after his first and two years after making his comeback from a two-year doping suspension.
© AFP 2010
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