Roger Federer says he’s not necessarily the greatest male singles player of all time, despite winning more Grand Slam titles than anyone else.

36-year-old Federer has claimed a staggering 19 during his career – even more impressive considering he recently went five years without winning one.

That’s three more than second-placed Rafa Nadal, which has understandably led to the Swiss acquiring the label of Greatest Of All Time.

But, modest Federer says it’s hard to tell just who was best, and that Grand Slam titles is by no means the only way of judging how good a player was – though he says he is happy with his own record.

“Like Bjorn Borg, he only went to Australia once or twice because it was during the Christmas [time], and he was happy at home instead of travelling,” Federer told Gulf News.

“I worked extremely hard to have a great career, and sometimes have chased records.

“But you know, it’s hard to judge who is the best of all time, you see Bjorn Borg, John McEnroe, Rod Laver, Rafael Nadal, Ivan Lendl, Jimmy Connors and Pete Sampras.

“There are so many players [who] did fabulous things, so I tried my best with my career.

“I didn’t expect myself playing maybe this well at this age. I’m happy with what I achieved, and hope I can keep going.”

Speaking of his rivalry with another contender for the tag of 'GOAT', Federer said a change in tactics has helped him improve his game against Rafa Nadal recently, although he’s taking nothing for granted despite winning the Shanghai Masters.

“I think I’m serving consistently better,” he continued.

“I get easier power ever since I switched to the bigger racket. I feel I’m connecting better on the backhand and I’m serving good.

“I think it was hard for me to consistently just keep on attacking with the backhand, but now it seems almost not a problem.

“But that’s no guarantee, he is gonna keep working. Rafael is a great player and extreme difficult to play against, because he can use his left hand do everything.

‘”But what I see is to win the title, not so much beating Rafael, but of course beating him is more special.”