Men's tennis is fast sliding from one of its greatest eras in history to a period of struggle.
Roger Federer dispatched Belgian David Goffin in under 90 minutes in the Australian Open 4th round
Source: Associated Press
For the best part of a decade sports fans have found whatever seat they can to watch Federer, Nadal, Djokovic and Murray run each other ragged in, usually, gripping five-set "epics"(excuse the over-used word to describe brilliant tennis matches).
Between the quartet, they've won 48 of the past 55 Grand Slam singles titles dating back to the 2004 Australian Open. Incredible.
But, over recent years all have battled concerning injuries or alarming form slumps (Federer himself even went five years without winning a Grand Slam, before producing one of the great career comebacks to win the Australian Open and Wimbledon crowns this year).
Federer (36), Nadal (31) and Djokovic (30) are all on the wrong side of 30-years-old and can't play forever – as much as we all wish they could.
While Nadal is in the semi-finals of the US Open, Federer was ousted in the quarter-finals by a resurgent Juan Martin del Potro. The other two haven't been spotted since being beaten in the last eight at Wimbledon.
Since, Djokovic has battled an elbow injury, while Murray had to withdraw from New York due to a hip problem and this week announced it will force him out of the rest of the year.
The current US Open has given us a glimpse of what men's tennis will be like without them and it's been a very deflated feeling.
With Federer and Nadal in the same half of the draw, the bottom half is glaringly empty. Giant South African Kevin Anderson will meet Spain's Pablo Carreno Busta in the other semi-final.
The average punter would be excused for asking who either of them are (Anderson has been a strong showing to the ASB Classic in the past few years while Carreno Busta has won three ATP Tour titles and previously only made it into a Grand Slam quarter-final once - this year's French Open).
Anderson's win over Sam Querrey in the quarters at Flushing Meadows may have gone deep into the night for four sets, but it was a boring serve and snore-fest – stark contrast to what we've seen on previous occasions between Federer, Nadal, Djokovic or Murray.
Of the seven Grand Slams won by those outside the Fantastic Four, Wawrinka's won three of them. However, he's now 32 and won’t have a huge amount of years left in his career either. The likes of Tsonga and Nishikori have challenged for titles, but, again don't excite like the big names.
There will be a superstar or two in the next generation of men's tennis stars. There always is. But four at once, gripping the sporting world, even non-tennis fans, month-after-month?
Not a chance. Dimitrov, Zverev, Čilić and Raonic have all been touted as players to watch for the future, while del Potro is exciting with his comeback - but it's hard to imagine that will go on for an extended period of time judging by his run of injuries.
The fact is none of them have the on court elegance of Federer, the endless energy, stamina and spin of Nadal or the all-round polished games of Djokovic and Murray at their peaks.
If there's one positive to take from all this – it’s that it may be slightly easier for Karl Budge to weave his magic once again and get one of Federer, Nadal, Djokovic or Murray to play in Auckland towards the twilight of their careers.
Outside of that, we have to enjoy it while it lasts because we're going from the penthouse to the outhouse in men's tennis at a rapid rate of knots.