The former Italy international used the two Tennis superstars to compare the Juventus and Barcelona forwards
Antonio Cassano likened Cristiano Ronaldo to Rafael Nadal and Lionel Messi to Roger Federer as the former Real Madrid forward praised the two football superstars.
Ronaldo and Messi have dominated the sport over the past decade, splitting the last 10 Ballons d'Or awards as former players, pundits and fans debate the pair's standing among the best ever.
And after Ronaldo swapped European champions Real Madrid for Italian giants Juventus in a sensational €100 million ($116m) transfer completed this week, Cassano used tennis greats Nadal and Federer to compare the 33-year-old Portugal captain and Barcelona icon Messi.