The last time someone younger than Stefanos Tsitsipas won the ATP Finals on his debut that was a 19 year-old John McEnroe 41 years ago, who possessed a similarly outrageous talent if a somewhat more volatile temperament.
Now there is another star in the making, with 21 year-old Tsitsipas bringing the 02 Arena to its feet by edging out Dominic Thiem 6-7 6-2 7-6 to claim the year-end event open to the season’s leading eight players.
There is much to admire in the all-round game of the Greek who first learned his trade by hanging around in the holiday resorts near Athens where his parents gave lessons to tourists.
Yet it is in the invisible area of the brain beneath those flowing Elizabethan locks that he is particularly impressive.
Having held out in eleven break points against Roger Federer in the semi-final he was the more controlled of these two players when they got to 4-4 in the sudden death tiebreak.
It is more than five years since men’s tennis had a new Grand Slam champion (Marin Cilic at the US Open) and when a fresh one is finally anointed it may turn out to be Tsitsipas.
His trajectory is swiftly heading that way, as this time twelve months ago he was winning the ATP NextGen Finals.
One year on he is pocketing a cheque for £2 million for winning what has been the best edition of this event in several years, its penultimate time in London.
‘Honestly I don’t know, I have no clue why I played so well in the second set,’ said Tsitsipas. ‘ I wasn’t thinking of much. I didn’t give him much options. First time playing a big event like this there were nerves, I’m so relieved.’
The arena was not quite sure how to split its loyalties between these two, perhaps partly because neither has ever gone past the fourth round of Wimbledon and they remain slightly unfamiliar to many in the UK.
The crowd would have expected to see at least one of Nadal, Federer and Djokovic, and with very good reason.
Incredibly, this has been the first tournament since early 2010 that has seen a final without any of the big trio, when all three have entered.
If it is not the Greek then it could be Thiem who, as ever, hit his backhand like someone manically trying to start a lawnmower.
He can consider himself unlucky, but then his opponent was well ahead on points, 110-93.
Neither player fits a mould, and this finds expression in the fact that both play with that single handed backhand, the stroke whose demise has been predicted for years but is now in safe hands for a generation.
The Austrian, with his fast bowler’s backside, generates great speed off both flanks while Tsitsipas is not exactly short of power when he needs to draw upon it.
The Greek also has ingenuity, as he showed when facing one of the two break points against him, at 3-3, in a desperately tight first set.
Rather than play safe he hit a kick serve on his second serve and surprised his opponent by running in after it to hit a volley winner.
He is no baseline clone, way more comfortable at the net than most of his peers.
He nearly recovered from 0-3 in the tiebreak, but missed a crucial backhand and was edged out 8-6.
The second set turned on his serve, which he began to aggressively go for. He won 16 out of 18 points when serving, the Austrian constantly on the back foot.
Tsitsipas kept his momentum going by breaking early in the third but was pulled back and the match headed inexorably towards the tie break.
The Greek got ahead for 4-1 but Thiem levelled up, only to be the player who blinked and made a mini-series of unforced errors at the end to lose in two hours and 34 minutes.