Astana may have ruled Fabio Aru out of the Giro d'Italia but Vincenzo Nibali still believes his rival can make the start line in Alghero.
Aru was forced to withdraw from next month's Giro after damaging his knee in a training fall, Astana stating on Monday he needed complete rest for 10 days.
Michele Scarponi was subsequently announced as Aru's replacement to lead the team in the 100th edition of the Grand Tour, but Nibali has urged his compatriot not to give up hope.
"Fabio, don't lose hope. Not yet," he said in an open letter to Aru in the Gazzetta dello Sport.
"Even if it's very difficult and perhaps even impossible, I think there's still a chance to see you at the start of the Giro d'Italia on May 5 in Alghero.
"You and I are the two big Italian riders for Grand Tours and everyone will miss out if you can't be in Sardinia.
"In my heart I hope that something can change during the ten days of rest that Professor Combi has prescribed.
"I'm really sorry about what happened. I think like a rider and so I know what it's like to dedicate months preparing for a goal as special as the Giro d'Italia that starts near your home, especially for us, who come from the islands, and so don't often get to race near our homes.
"If everything had gone well, you would have definitely been a contender for the pink jersey."
He added: "I'm not a doctor but sometimes we're able to recover faster than people expect. Maybe things will be better in a few days time.... Fabio, don't give up hope, even if everything seems lost. Miracles do happen and I really hope to see you at the start of the Giro 100.
"I just hope there's a chance you can change your mind. Everybody knows what has happened and nobody would expect you to be at 100 per cent.
"But perhaps you can try to ride and then leave the Giro if it becomes impossible to continue. Whatever happens, the Giro could be useful for the Tour de France and for the future."