Roger Federer has hit more aces than Rafael Nadal and Novak Djokovic combined

The GOAT debate in tennis continues to rage on, with Roger Federer, Rafael Nadal and Novak Djokovic locked in a tight race to finish with the most Grand Slam titles. And the discourse usually involves a number of sub-plots - often in the form of statistics - that purportedly prove the superiority of one over the other two.

When talk veers to the serve of the three men, most fans know there can only be one winner. But the extent to which Roger Federer bosses this category is almost too staggering to be true.

Federer's career ace tally till date is more than the combined sum of his fierce rivals Rafael Nadal and Novak Djokovic. Yes, you heard that right; the Swiss has hit 11,365 aces so far, which is more than what Djokovic (5,722) and Nadal (3540) have together accounted for - 9,262. And the difference is quite too: Federer has hit 2,103 more aces than his fellow GOAT candidates have hit combined.

Roger Federer's crosscourt forehand and slice are a treat to watch for any tennis fan, but the one unheralded aspect of his game has been his impeccable serve. And it is technically sound too; Federer's service motion is the perfect template for any youngster to follow.

With a typical continental grip, the movement is perfectly fluid and smooth as Federer transitions from a low toss to a full-on accelerated "whip-like" impact on the ball. Many say it is like watching poetry in motion.

How does Roger Federer's serve compare with the giants of the tour?

Ivo Karlovic (L) and John Isner (R), the only 2 players who have hit more aces than Roger Federer

If we were to take a look at ATP's all-time list of ace leaders, we would find that it is dominated by players who are over 6'6" in height. That is quite natural, as there is a very high correlation between the height of a player and the speed of the serve - and consequently the ace count.

The fact that Roger Federer stands third in the all-time list - well ahead of powerful servers like Andy Roddick, Pete Sampras, Sam Querrey, Goran Ivanisevic and his own coach Ivan Ljubicic - speaks volumes about the greatness of the shot.

At 6'1", Federer is the shortest player in the top 20 of the all-time ATP ace chart. And the only players above him - Croatian giant Ivo Karlovic and American John Isner - are both above 6'8" in height.

As can be seen from the list, Roger Federer is far above his nearest rivals Rafael Nadal and Novak Djokovic, who are at the 23rd and 65th spots respectively. In his marathon Wimbledon 2009 final against Andy Roddick, Federer hit an incredible 50 aces - a feat that has been achieved by just a handful of other players.

Roger Federer's serve is a perfect blend of Sampras' and Agassi's serve: Andy Roddick

Roger Federer (R) with Pete Sampras, Andre Agassi and Rafael Nadal

On numerous occasions in the past, ex-players and legends of the sport have stated that the most underrated but effective part of Federer's game is his serve. In a recent interaction, American ace machine Andy Roddick complimented the Federer serve by saying that it is the perfect blend of the Pete Sampras and Andre Agassi serves.

"Andre Agassi was a player who messed around with his ball toss and the pacing of his serve. Pete Sampras was a more powerful server and had very good placement. I feel that Roger Federer’s serve is a hybrid of Pete and Andre,” Roddick said.

According to Roddick, a major part of what makes the Federer serve so effective is its disguise. The Swiss is not among the hardest servers on tour, but the fact that he has so much variation and accuracy up his sleeve makes him a nightmare to face.

“Roger had the incredible ability to throw any kind of serve at any time. He could throw 97 mph kick serve one time then throw a very powerful serve out wide. He was never predictable and that was what was so frustrating,” Roddick said.

Federer and his legion of loyal fans around the globe will be hoping that his serve continues to deliver, and aid him in his conquest to add more trophies to an already glittering cabinet.