17-time Grand Slam champion Roger Federer has tipped Argentine Juan Martin Del Potro to be the World No.1 in 2013, if he stays fit. The Swiss played several played several matches against Del Potro in 2012, with both playing fantastic tennis.

“I think your goal should be, at least to try and reach a top 4 or 5 ranking,” Federer said. “Juan Martin was playing very well this year. I hope he can maintain that level in 2013 and be more comfortable physically, and not get injured. Because unfortunately he was hurt a long time. He can fight for No. 1. I played against him many times this year, and they were very difficult matches, exciting.”

Federer and Del Potro have shared a healthy rivalry and have engaged in some of the best matches in recent years. The Argentine had defeated Federer in the 2009 US Open final to claim his first and till date only Grand Slam trophy.