Vincenzo Nibali warned that Tadej Pogachar's road to victory in the Giro d'Italia is not as straightforward as it may seem. The Slovenian will make his Giro debut next month as one of the favorites to win the overall, but Nibali insisted that the Corsa Rosa is always full of unexpected developments.

"He will have to sweat for the overall win. In the Grand Tours, nothing is really easy," Nibali told La Gazzetta dello Sport.

Like most, Nibali expects Pogachar to get off to a fast start in his Giro debut. The summit finish in Oropa on stage 2 will be an early chance for him to make his mark on the race.

However, the two-time champion stressed that despite this year's route structure, the Giro is a marathon, not a sprint.

"It has to be perfect for 21 days," he said. Of course, I don't want to wish Taddei bad luck. But generally speaking, just one day of bad luck, which can happen to anyone, can change a lot." [For example, there are days of extreme cold in the Giro. Even the great champions have constant difficulties in the Giro. They make a difference by dealing with negative moments without cracking.

Pogachar's expected Tour de France rivals Primoz Roglic, Remco Evenpole, and Jonas Vingegaard are not in the Giro. Last year's runner-up Geraint Thomas (Ineos) and Romain Bardet (DSM-Filmenig-Post NL) are Pogachar's most obvious rivals, and a number of young talents, including Sian Uitdebroeks (Visma-Ries-a-Bike), will also be racing.

None of them, however, seemed to be able to outperform Pogačar in a head-to-head race, and even Nibali called for ingenuity from his Slovenian rivals.

"You have to put out of your mind the idea that he is unbeatable, even if it seems that way," Nibali said, adding that even his most dominant Grand Tour victory, the 2014 Tour de France, was not as serene as it appears from the outside.

"In a Grand Tour, you can't have everything under your control. I would say this to my rivals in Taddej: direct confrontation is very difficult and you have to be creative. The route and overall situation of the Giro can help you be more inventive than in the Tour."

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