Rod Laver is the only player in history —male or female—to win the Grand Slam twice.
The Hall of Famer favors Novak Djokovic to win Roland Garros this month, complete his second Novak Slam and hold all four major championships simultaneously.
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"I'm probably favoring Novak at the moment and then Rafa and then it goes down the line," Laver told the media in Paris. "Then it's who's going to play who."
If Djokovic wins Paris, he would claim his 16th career Grand Slam title, which would put him one behind 17-time Grand Slam champion Rafael Nadal and four majors short of Roger Federer's men's record of 20 major singles titles.
Laver said regardless of whether Djokovic wins Paris again this month, he is already equal to Federer and Nadal as a champion.
"You know, they all play a little differently," Laver said. "You look at their record, which is really how you summarize who the best players are. And I think Novak is certainly equal to, I think you look at three of them, you look at Novak and Rafa and Roger.
"To me, they are three just huge champions. I don't know what their record against each other is all the time, but it's amazing to see, you know, players like that that are so in love with the game. They're prepared to put the effort in and know about the game, as well as being able to play it at its best. So I don't know.
"I don't know as I put one above the other because of the fact that tennis was just so fortunate to have almost... and with Murray, and adding Murray in there, as well, so you have four great champions that are representing the game of tennis."
Laver, who sat in Federer's box yesterday during his straight-sets win over Leonardo Mayer, cast doubt on whether the 2009 champion can win a second Roland Garros crown and join Laver himself and Roy Emerson as the third man to win all four majors at least twice.
"I don't know whether Roger's... he's certainly in it and he's certainly playing well, but I don't know if anyone has really pushed him yet," Laver said. "I think he'll be pushed a lot more when it comes to some of the younger players coming up through the ranks.. I think someone like Rafa is going to be tough if Roger and those two meet."
Photo credit: Tennis Australia