Until Roger Federer [Images] wins the French Open and tears a Spanish thorn from his side he cannot be considered an all-time tennis great, according to former world number one John Newcombe.

Federer snatched a fourth Wimbledon [Images] crown on Sunday with a four-set victory over Rafael Nadal [Images], his claycourt conqueror at Roland Garros last month.

However, Sunday's victory was only a second in eight matches against the Spaniard and that is one thing the Swiss must put right to take his place among the sport's greats, Newcombe said.

"There's no question that he should be talked about but there is a question mark there now because he's losing six matches to two to Nadal," the Australian winner of seven Grand Slam titles said.

"To be in the top three or four of all time you have to dominate completely in your era," he said on Sirius satellite radio.

Aged 24, Federer has won two US Opens, two Australian Opens and four Wimbledons, and was runner-up at this year's French Open.

Newcombe, whose career spanned the 1960s and 70s, matched Federer's US and Australian hauls but won one fewer Wimbledon crown and never progressed beyond the quarter-finals on Parisian clay.

"Roger -- if you want to talk about him on hard court, on grass -- yes, you can debate that. But you can't put him up there because he has not been able to win the French Open and Nadal has not only been beating him on clay, he's beaten him and matched him on hard court.

"So if you're going to put Federer there, you've got to put Nadal there.

"But Roger Federer's career is only halfway through. He's got another four or five years. Let's see what happens by the end of his career."

Pete Sampras, winner of a record 14 Grand Slam titles including seven Wimbledon crowns, was judged in the same harsh light by the former Australian Davis Cup captain.

"Pete Sampras cannot go down in that category because the best he ever did at the French Open in 11 tries was one semi-final," Newcombe said. "So there's no way he can be categorised as one of the best three or four of all time."

Only five men have won all four Grand Slam tournaments at least once -- Don Budge and Fred Perry in the 1930s, Rod Laver and Roy Emerson in the 1960s and Andre Agassi [Images] in the 1990s.

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