Former Giro winner Ivan Basso took over the leader's pink jersey after Michele Scarponi won an epic 19th stage of the Tour of Italy on Friday.
Basso finished second on the day's stage over 195km from Brescia to Aprica but came home more than three minutes ahead of David Arroyo to move to the top of the overall standings.
Other contenders such as Australian road race world champion Cadel Evans, Kazakh Alexander Vinokourov and former Tour de France winner Carlos Sastre also lost more than three minutes.
Basso now leads Arroyo by 51 seconds with the Italian's compatriot and Liquigas team-mate Vincenzo Nibali, who finished third on the stage, third at a distance of 2min 30sec.
Evans (4:00) is fifth overall with Sastre (5:32) sixth and Vinokourov (6:02) eighth.
"I could have tried to get some distance between myself and Nibali and Scarponi on Mortirolo (the penultimate hill) but it wouldn't have been a clever choice," said Basso. "Their help in the final ascent to Aprica was very useful. I wasn't worried coming downhill. I knew we could make the difference in the ascent to Aprica, in the final 10 kilometres."
Scarponi said: "I've won a very tough stage and I can only be delighted. My legs are killing me but I'm really riding high. Tomorrow there'll be another great fight."
It was a classic stage that provided thrills throughout and lots of drama as the gap on the road, and in the overall standings, between Basso and Arroyo ebbed and flowed.
The crucial moment came on the penultimate climb, the legendary and gruelling Passo del Mortirolo. Arroyo was quickly dropped by the contenders as Liquigas turned on the gas. Sastre and Vinokourov were next to be dropped off the back before Evans too failed to keep the pace by now being set by Basso himself.
Only Nibali and Scarponi could stay with him and when they caught and passed Stefano Garzelli, who had broken away on the previous climb, they were at the front and riding for time.
They went over the top with a 55sec lead over Vino, who had broken free of his companions, with Evans 1:30 back and Arroyo at 1:42.
Arroyo put in a breathtaking descent, though, and by the bottom he had joined Vinokourov and cut the lead to just 38secs, boosting his chances of holding onto pink as he started the day 2:27 ahead of Basso.
Evans had managed to get back up to Sastre and Frenchman John Gadret and when the three joined Vino and Arroyo, they appeared to have the group needed to reel in the three leaders. However, only Arroyo and Evans seemed willing to work with Sastre occasionally pulling a turn.
Up front Basso and Nibali were going hell for leather with Scarponi putting in some work as they reached the closing stages.
The two Liquigas riders were far better organised than the chasers and suddenly, over the last 12km or so, the gap started to increase quickly.
It was heart-breaking for Arroyo, whose grit and determination to climb back after looking dead and buried at the bottom of the Mortirolo was a wonder to witness. But by the time he reached the line, losing 3:06 as well as Basso's 12 bonus seconds for finishing second, he looked a beaten man.
With a mountain stage to come on Saturday and Sunday's short time-trial, only a disaster looks capable of denying Basso a second Giro crown.
© AFP 2010
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