Madrid - Alberto Contador believes former rival Chris Froome is ready to win a maiden Giro d'Italia title next season, and then follow it up with a record-equalling fifth Tour de France crown.
Froome won the Vuelta a Espana for the first time in September to join Frenchmen Jacques Anquetil (1963) and Bernard Hinault (1978) as the only riders to win the Tour and Vuelta in the same year.
But the Briton has yet to win the Giro, a race he has featured in just twice and not since his disqualification from the 2010 edition for holding onto a motorbike.
"He's an extremely strong rider and I see him perfectly capable of winning the Giro," Contador told reporters in Madrid on Tuesday.
"He has a very strong team that can support him perfectly, whether it's on the Giro or on the Tour," added the 34-year-old Spaniard, who retired from cycling in October.
Froome has yet to commit to racing in next year's Giro, which will start in Israel on May 4, but Dutch newspaper De Telegraaf reported Monday that he would attempt a Giro-Tour double in 2018, 20 years after the late Marco Pantani was the last rider to achieve the feat.
Froome could become just the third man in history to hold all three Grand Tour titles at the same time -- after Belgian Eddy Merckx (1972-73) and Hinault (1982-83) -- but Contador said it would be difficult to eclipse past greats as the best rider in history.
"There have been great champions in the past, even if it's true that cycling has evolved," said Contador, one of just six cyclists to win all three Grand Tours.
"But I think that a legend such as Eddy Merckx, for example, is difficult to overtake."