NOTE: We are only discussing the greatest MALE tennis player of all time.
The FEMALE GOAT is between Marina, Steffi Graf, Serena. And Steffi wins it as she is the only female player in open era to win a calendar grand slam. And yes before anyone points out, she also won the Olympic gold, but thats not a prize money event, so am not taking that into criteria for GOAT, which am basing on pure professional prize money events.
Now, in my view, the most basic qualification criteria for GOAT or GREATEST TENNIS PLAYER OF ALL TIME is to win a Major or slam in all 3 surfaces. That automatically (and unfortunately) rules Rod Laver out as he won only on grass and clay. It is arguable if he would have won had majors been played on hard courts in 60s.
Only the following 6 players have won Tennis Majors in ALL 3 surfaces (clay, grass, hard court) in the Open Era:
The great Jimmy Connors! Yes, while he didn’t win French Open, not many know that his US Open triumph in 1976 came when it was played on clay. YES.. for 3 years, the US Open was played on clay as the hardcourt stadium was being renovated. And he beat BORG in that clay court US Open final. Borg as we know was a clay master!
Connors obviously also won US Open on hard court and Wimbledon on grass.
The sportive Wilander we know didnt win Wimbledon, but he did manage to win the Australian Open in 1983 and 84 when it was played on grass. He has also won the French Open on clay and the US Open on hard court.
And then come the modern greats – Agassi, Federer, Nadal and now Djokovic – have all completed a “career grand slam” (all 4 majors played in 3 surfaces).
Out of these 6 players, Novak Djokovic is the ONLY PLAYER to win 4 CONSECUTIVE MAJORS in a row across 3 surfaces. This makes Djokovic a massive GOAT contender.
But despite that, Nadal remains, the only male player to win 3 consecutive MAJORS IN 3 DIFFERENT SURFACES within a single calendar year when he won the French Open, Wimbledon and the US Open in 2010. No player has ever done this to date.
And Federer of course has 17 majors. But his poor losing record to Nadal in head to head really puts a dampener on his GOAT claims.
BUT if Djokovic wins WIMBLEDON, then he will equal Nadal’s under-rated record above and also become the first to win 5 majors in a row. UNPRECEDENTED.
And if he wins the US Open, then he wins the “calendar grand slam”, the ONLY male player to do it across 3 surfaces. And also winning 6 majors in a row in that process.
Djokovic has ticked almost all other boxes: better head to head against the top 4 best players of his era: Federer, Nadal, Murray and Wawrinka and barring one, ALL his Major wins he faced another major winner as opponent. Plus, he has won more ATP Masters Series titles than anyone else.. and is also the first to cross $100MN prize money.
Just Wimbledon and US Open wins this year stand between Djokovic and the crown of UNDISPUTED Greatest Of All Time (GOAT).