WIMBLEDON, England — The last man to win a true Grand Slam in tennis thinks it could happen again.

Rod Laver won all four of the sport's most prestigious tournaments in 1962 and 1969, and he said Sunday at Wimbledon that Roger Federer and Rafael Nadal are both capable of matching the feat.

Invited by the All England Club to attend Sunday's Wimbledon final between Federer and Andy Roddick, Laver said Federer "would have won a Grand Slam if Rafa wasn't there."

Federer won three of the four major titles in 2004, 2006 and 2007. The latter two years, he lost to Nadal in the French Open final.

"The Australian, the U.S. and Wimbledon was pretty easy for him, when you look back at his career, winning three of each one," Laver said. "But Nadal came along and pushed him back."

Federer entered Sunday's match with 14 Grand Slam singles titles, tied with Pete Sampras for the most in history. Federer began the day with five titles at Wimbledon, five at the U.S. Open, three at the Australian Open and one at the French Open.

Roy Emerson won 12 major championships, and Laver won 11, although he was barred from competing in those tournaments from the time he turned pro in 1963 to the start of the Open era in 1968.

Don Budge is the only man other than Laver to win a calendar-year Grand Slam, doing it in 1938.

"It all has to line up in a way that you have to be fortunate to play your best tennis at the right time. That's the way it is," Laver said.

As for the debate about whether Federer might be the greatest player ever, Laver said that's the wrong way to frame the discussion.

"I've always thought that you're the best in your era. That to me is a pretty good compliment to your game, to your tennis, over your career. You know, if Roger gets to 16, 17 Grand Slams, you know, people in the press are the ones that are wanting to say it: Who's the best ever?" Laver said. "It's hard for anyone, I think, to come out and say who's the best ever."

The 70-year-old Laver, a left-hander from Australia who now lives in California, was effusive in his praise of Federer and his game.

"It's amazing what sort of shots he can come with from impossible positions. It's a great feeling of being able to watch the talent that he has and the opponents that he beats comfortably," Laver said.

"It's great that tennis has someone like Roger. We always look at Roger, he and Tiger Woods are good friends, fighting to see who can have the best number of Grand Slams in golf and tennis."