Jack Nicklaus believes Tiger Woods still has the talent and work ethic to surpass his record of 18 major titles - but feels the number of fearless young contenders around will make the task difficult.
Woods goes into this week's Open at Royal Lytham & St Annes looking to win his first major since the 2008 US Open.
But the 36-year-old has recently recaptured some of the form that deserted him amid his much-publicised personal problems.
Woods overtook Nicklaus in the all-time PGA Tour winners list this month with his 74th title, and third in recent months, and is now second only to Sam Snead, who won 82.
Woods has won 14 majors and Nicklaus would not be surprised to see his own feat come under pressure yet.
Nicklaus said: "I've said many times that his work ethic is so good and his desire to pass my record is there, and I think he is still plenty young enough.
"I believe he can but he has still got to do it. As each tournament passes he has less chance."
Nicklaus is eager to hang on to his position as the greatest in the top four tournaments and he believes the emergence of 2011 US Open winner Rory McIlroy among other promising players could help keep him safe.
"I don't think the guys are scared of him like they were," Nicklaus said.
"When you looked at it six, seven years ago, under the age of 30, Tiger was the only player in the US tour that had more than one win.
"Now you've got multiple guys with multiple wins under the age of 30.
"The game has grown to a degree that we have more and more good players.
"With Rory coming along, Rickie Fowler coming along you've got Dustin Johnson, Keegan Bradley, Jason Day, Luke Donald. Every week you have another, Marc Leishman the other week.
"That makes it more difficult for Tiger to do what he has to do.
"There isn't a player playing today who has five majors.
"But the guy is so talented, that's why I think he has a chance."