Cape Town - Novak Djokovic was hailed as "one of the greats of all time" by John McEnroe as he again claimed the year-end world number one spot with a victory at the ATP Tour finals on Friday.
Fellow seven-time grand slam winner McEnroe paid his tribute before Djokovic demolished Tomas Berdych 6-2 6-2 at the O2 Arena, not just roaring into Saturday's semi-finals but also sealing the world's top spot for the third time in four seasons.
The achievement represents a period of consistent excellence not matched since Roger Federer was honoured five times in six seasons between 2004 and 2009.
Djokovic becomes only the seventh player in the game's history to have achieved the milestone three times, following Pete Sampras (6), Jimmy Connors and Roger Federer (5), Ivan Lendl and McEnroe (4) and Rafael Nadal (3).
It left McEnroe, one of a distinguished group of former number ones attending the on-court ceremony celebrating the Serb's achievement, to note the magnificence of Djokovic's game and to conclude he could improve and reign for seasons to come.
Reminded of his own experience of breaking into the duopoly of Connors and Bjorn Borg in the late 1970s, McEnroe reckoned Djokovic had "done an incredible job" by now being mentioned in the same breath as Federer and Nadal.
"That shows me that he has become one of the greats of all time. He is going to be there a couple more years. He looks so rock solid, it's incredible," said McEnroe.
"If Rafa is not healthy, that might open the door for him to win the French Open (the one grand slam to elude Djokovic). I would say the greatest players that ever lived are Roger (Federer) , Rafa (Nadal), my idol Rod Laver and Pete Sampras.
"I wouldn't put him there yet but in the top 10 and maybe he is moving higher as each minute goes (by). The good news (is that) he is getting better and by the time I was his age I was getting worse!"
After what seemed an almost routine demolition of Berdych, the 27-year-old Djokovic thrust his arms towards the Dome roof and appeared quite emotional about his achievement.
"I got married, became a father recently and it's the most beautiful thing in the world," he told the crowd.
"To be able to stand next to this trophy and to have the crown for all the achievements in this 12 months, it's very fulfilling and it's a joy."