Colombia's Nairo Quintana is ready to attempt a rare Giro d'Italia/Tour de France double, and warned rivals the first shots in the battle for an epic pink jersey could be fired on Tuesday.
Quintana, the first Colombian to win the Giro d'Italia, in 2014, will start the 100th edition on Friday tipped to beat former two-time winner and defending champion Vincenzo Nibali of Italy to the top step of the podium.
An eventual triumph in Milan on May 28 would hand the 27-year-old climbing specialist impetus for his attempt to add the yellow jersey to a pink jersey in the same calendar year - a feat last achieved by deceased Italian great Marco Pantani in 1998.
Due to the simultaneous difficulties of recovering from the Giro -- a "harder race than the Tour," said Quintana -- and keeping top form for July, it is considered stage racing's Holy Grail.
This year's Giro route, which also includes two individual time trials, will give Quintana ample opportunity to test his rivals, mainly in a climb-heavy third week that Nibali has described as "terrible".
But the Colombian said Tuesday's fourth stage, a 181 km race which begins in Cefalu, Sicily and finishes on the slopes of Mount Etna, will give him an early idea of who will pose a threat once the race heads into the rarified air of the high mountains where Quintana usually excels.
"It won't be decisive, but the stage to Etna is important because it will give me an indication of my form and an indicaton of who the real GC (general classification) contenders could be for the final week," said Quintana.
The fourth stage comes a day after the first of three rest days on Monday, but Nibali warned it will be even harder than the stage to Etna -- the tallest active volcano in Europe -- he raced in 2011.
"We have 4000 metres of vertical climbing to do and it comes after a few nervous stages in Sardinia," said Nibali.
"It's a different ascent compared to six years ago. This way is harder, and it comes after a rest day."
Given he has not yet won the Tour de France, finishing as the race's best climber in 2013 and best overall young rider in 2013 and 2015, Quintana's double bid could be regarded as ambitious.
At July's Tour de France, for example, the Colombian will be up against the likes of former three-time winner and defending champion Chris Froome of Britain.
But Quintana, who has raced for Movistar since 2012, said the secret to unlocking victory in the world's most prestigious bike race is controlling how the peloton race it.
When it comes to the Giro, the roads and climbs are actually more difficult. Quintana, though, is still relishing the chance of a second triumph.
"In terms of racing, the Giro is harder than the Tour de France. It is the way the riders race the Tour that makes it difficult," he said.
"I've never attempted to win the Giro and the Tour in the same year, so I don't really know what it will be like.
"It's the 100th edition of the Giro, so I was never likely to miss it. I'm happy to be here representing all of Colombia, and Latin Americans.
"But to do the double, you first have to win the Giro! We'll see at the end of it all whether I succeeed or not."