Tim Henman says Novak Djokovic can settle GOAT debate by winning Calendar Slam, but claims Federer's popularity remains unmatched

For many, Novak Djokovic is already the greatest tennis player of all time. The Serb is currently level with Roger Federer and Rafael Nadal on 20 Grand Slam titles, but has spent more weeks at the World No. 1 spot than his two rivals.

Djokovic also has a superior head-to-head record against both Federer and Nadal and is the only member of the Big 3 to hold all four Majors simultaneously.

But for many tennis fans who sit on the fence, the Serb winning a 21st Grand Slam at the US Open would seal the deal. Lifting the trophy in New York would not only give Djokovic sole ownership of the Grand Slam record, but it would also make him the first man since Rod Laver to complete the Calendar Grand Slam.

Former World No. 4 Tim Henman believes Djokovic would leapfrog his rivals in the GOAT race if he wins in New York next month. However, Henman reckons Federer is untouchable when it comes to popularity.

The Swiss legend has won the ATP Fan Favorite Award for 18 consecutive years (2003 to 2020). That could extend to 19 in December even though Federer has played only five events in 2021.

“There are two different conversations to be had about the greatest player, the best player, that comes down to a numbers game and Djokovic will win that,” Henman told the Tennis365 website. “If you are talking about impact and popularity, it is a one-horse race and there is no doubt that Federer is the most popular player that has ever played our sport.

“But you have to say if Novak goes to 21 and Federer and Nadal are on 20, you would have to say Djokovic is leading that debate over who is the greatest, but throw in a Calendar Grand Slam and it would elevate him to a different level. He would then be the best male player of all time.”

The meltdowns Djokovic had at the 2020 US Open and Tokyo Olympics might help him now: Tim Henman

Novak Djokovic walks off the court after being defaulted due to inadvertently striking a lineswoman with a ball during his fourth-round match against Pablo Carreno Busta at the 2020 US Open

Novak Djokovic has had an incredible first six months in 2021, winning the Australian Open, French Open and Wimbledon titles. That set the Serb up for a Golden Slam.

However, things went off the rails at the Tokyo Olympics, where he was first defeated by Alexander Zverev in the semi-finals, and then by Pablo Carreno Busta in the bronze medal match. During his match against the Spaniard, Djokovic smashed his racket several times and even flung it into the empty stands.

Henman believes the Serb's meltdown in Tokyo, as well as the one he had at the US Open last year that led to his disqualification, may have been a good outlet for the Serb. Henman claims getting these out of his system could help Djokovic stay focused in New York this year.

“Now there is so much on the line for Novak and for me, the meltdowns he has had at the US Open last year and at the Olympics a few weeks ago might help him now. He has got them out of his system now," Henman said.

"That will focus his mind even more and I really feel the stars are aligning for Djokovic and he is going to be incredibly tough to beat in three out of five-set matches."