Demise of 'Big Four' puts tennis chiefs in desperate search for new hero
Winter is coming for the sport of tennis. Roger Federer, the sun king who has ruled the game for much of the past 15 years, might still be glowing like a radioactive isotope. But the golden generation - as a collective - has reached the end of the line.
Andy Murray's career-threatening hip injury marks the death knell for the Big Four. And it is not as if his peers are faring much better. Novak Djokovic and Rafa Nadal have yet to take to the match court this season.
The same goes for Stan Wawrinka, who turned the four into five for a few seasons with his big heart and his booming backhand.
But what, or who, will follow this God-given group? A period of instability feels inevitable; an interregnum to match the one that marked the end of the Pete Sampras-Andre Agassi era in the early 2000s.
There were five one-hit wonders, in Grand-Slam terms, between 2001 and 2004, including such long-forgotten names as Thomas Johansson and Albert Costa. Could another wave of left-field winners be on the way?
Or younger winners, at any rate. Tennis used to produce teenage champions on a regular basis, from Mats Wilander through Boris Becker to Michael Chang. Yet no man born after 1988 has claimed a Major title.
How do we explain this quirky stat? The sympathetic view would be that tennis's great quadropoly has strangled the life out of their natural successors: players like Kei Nishikori (born 1989), Milos Raonic (1990) and Grigor Dimitrov (1991).
But there is a tougher way of reading this phenomenon. Federer stated it in July, on the morning after his latest coronation at the All England Club.
"Since my generation and Rafa's generation," Federer said, "the next one hasn't been strong enough to push all of us out."
Will the baton now bypass tennis's inbetweeners altogether? That was the prediction made by John McEnroe four years ago, when he pointed out that Raonic and Dimitrov "have been beaten up a little bit, maybe too much".
Which brings us to the 'Next Gen' concept. Over the past season or two, the Association of Tennis Professionals has started pushing a talented group of U-21s, all collected under this modish label.
Having done without succession planning for years, the ATP's suits are painfully aware that their four golden geese might stop laying at the same time. And who would they put on the posters then?
In November, the first edition of the Next Gen ATP Finals was staged in Milan. Open only to players born in 1996 or later, the event made an uncertain start when a squad of pole-dancer lookalikes took over the draw ceremony.
Still, once the embarrassing headlines had died away, the matches were good enough to transcend the gimmicks (no-let serving, automated line-calling, fast-four scoring) that surrounded them.
The Next Gen are led by Alexander Zverev, already the world No 4, who is shaping up as Germany's best player since Becker.
The supporting cast, especially Russia's Andrey Rublev and Canada's Denis Shapovalov, are superb physical specimens. And the geographical spread extends from the USA's Jared Donaldson to Milan's first champion Hyeon Chung - a rare example of a South Korean who prefers real sport to eSport.
Meanwhile, two young talents from Grand-Slam nations - Great Britain's Kyle Edmund and Australia's Nick Kyrgios - who yesterday produced a spellbinding performance to lift the Brisbane International crown - missed out narrowly on Milan, having been born a year too early.
Even so, they still add to the sense of critical mass that surrounds this peer group.
Yet not everyone is convinced by Next Gen's collective potential. One leading coach - who preferred not to be identified - said that the young pretenders are made from different stuff to their ageing predecessors.
"These kids are athletic," he said, "and they can hit the ball super-hard because they've been trained well biomechanically. But the amazing thing is that they don't actually watch tennis!"
It was a fascinating viewpoint, if a somewhat pessimistic one. So for a second opinion, I consulted Ivan Lendl - a man who should be perfectly placed to judge. Lendl has worked not only with Murray but also for the US Tennis Association, where his teenage charges include Sebastian Korda, son of 1998 Australian Open champion Petr.
"I agree to a certain extent," Lendl said. "There are so many distractions these days. But I believe very strongly that in the right circumstances - by which I mean the right upbringing and surroundings, combined with proper coaching on and off the court - we will see players in the future who are extremely focused.
"What you have to keep in mind is that the Big Four are very special," added Lendl."Whatever sport you're talking about, groups like that don't come around too often."