Sampras backs Federer

Sampras, in Athens to play in an over-30s tournament series organised by fellow American Jim Courier, said current rankings leader Federer could also win more than his seven Wimbledon crowns.

"He is the best player in the world. He is going to go on and break all my records," Sampras told reporters. "He can win 16 grand slams."

Sampras, who retired after his 2002 U.S. Open victory, won a record 14 grand slams including seven Wimbledon crowns, three more than Federer's current haul. Sampras' Wimbledon record ties Willie Renshaw's, a player in the 1880s.

"Federer is phenomenal on the surface (grass)," Sampras said. "I think he can win seven or eight depending on how much he wants to go on."

Sampras said Federer's mental and physical strength would put him in a league of his own for the next few years, despite his split with coach Tony Roche last week.

"He is the strongest for now and will be for the next couple of years," Sampras said.

Federer played his childhood idol only once in a competitive tournament in the fourth round of Wimbledon in 2001.

Federer won the match 7-5 in the fifth set, ending Sampras' 31-match winning streak at the All England Club.