Something pretty heady is happening at this year’s Wimbledon Championships, made all the more remarkable by the fact we are taking it for granted. In the first week of July, Roger Federer will walk onto Centre Court the clear, undisputed favourite for the men’s title, and his ninth Wimbledon crown. This status reflects Federer’s recent form and the plight of his rivals. Novak Djokovic can barely string two wins together, Rafael Nadal hasn’t been a contender on grass since 2011, and Andy Murray hasn't even made the draw. None of the younger players have yet to seriously challenge for a Slam, let alone claim one. All eyes turn to Federer; a million hands are clasped in anticipation. After the triumph of 2017, can the king hold onto his throne?

Well if you want predictions, look elsewhere. This article comes bearing one message, and one message only: enjoy it. Whether a tennis fanatic or a casual fan, whether you worship at the church of Roger or cheer for the conquistador Nadal, if you find yourself watching tennis sometime over the next fortnight then appreciate the spectacle in front of you: the two, perhaps three greatest players of all time, and the finest Britain has ever produced, all competing in the same draw. This isn’t normal. Men’s tennis over the last 15 years has been anything but normal. And the end of an era is painfully near.

While Nadal and Djokovic have chiseled their names across the record books, it is Federer who has transcended not only tennis but sport itself, inadvertently creating his own literary genre with the likes of David Foster Wallace’s seminal Roger Federer as Religious Experience – still the pinnacle of modern sports writing, and surely Foster Wallace’s most widely read work. Everybody loves Roger: academics see fundamental human truths in his forehand, grandmothers swoon over his impeccable manners, journalists strain to write prose as graceful and fluid as his movement on court.

The fact we’re even witnessing Federer play Wimbledon in 2018, let alone play Wimbledon as the favourite, is more than a little ridiculous. He’s 36; he should be long gone. Time doesn’t affect Roger Federer the same as other athletes, gloriously proved by his recent Australian Open triumph. (Whatever happens, we’ll always have Oz.) And his last four Wimbledons offer further encouragement: it’s final, final, semi-final, winner since 2014.

But still. He’s 36. And while time mightn’t affect Roger Federer the same as other athletes, time still affects Roger Federer. One injury could finish him. Or a rapid deterioration in his talents, a sudden lurch into middle-age. Federer says he wants to play until 40, but such ambition comes easier when you’re taking out your greatest rival in a Grand Slam final; start losing to journeymen in the first week and the armchair can only look more comfortable.

Many great tennis matches await us in the years ahead, but none of them will be Federer vs Nadal 2008

Now here’s the (quite possible literal) million-pound question: what happens to tennis after Federer plays his final match? When he walks off Centre Court for the last time (surely it can only be Centre...), his departure will not only signal the end of tennis’s greatest player but also tennis’s greatest era. What next?

In 1974, Hugh McIlvanney wrote of the Greatest of all, Muhammad Ali: “His passing will surely have a cataclysmic effect. The championship he holds can never hope to mean as much without him.” The passing did, and championship still doesn’t, despite the best efforts of Tyson, Lewis and now Joshua. There’s a simple answer to the question: how do you follow the greatest of all eras? You don’t.

So while tennis will still be played ten years from now, how can a Grand Slam without the names Federer, Nadal and Djokovic in the draw invoke quite the same urgency as the titanic battles of the recent past? Yes, we’ll have Kyrgios, Zverev, Thiem, fine prospects all, but it’s a helluva leap from fine prospect to all-time great. Ten Slams, say. Here’s a sobering statistic: the last man beyond the You Know Whos to win more than three Slams was Andre Agassi, who won his eighth at the Australian Open – in 2003.

Many great tennis matches await us in the years ahead, but none of them will be Federer vs Nadal 2008. Of course very few matches get to be Federer vs Nadal 2008, although sometimes they compensate by being Federer vs Nadal 2007 or Federer vs Nadal 2017 or, if you must, Nadal vs Djokovic 2012. That option won’t be there anymore. The narrative, the history, the sense of inhabiting the pinnacle of what tennis, sport can be – all that is soon gone. And as a result, everything will appear diminished, both dramatically and quite possibly financially. How much of the world will switch on for a Raonic vs Thiem final? How many books are written about the age that follows the golden age?

Which brings us back to the original point: cherish this Wimbledon fortnight. Cheer for your favourite, curse every dropped game, every missed shot, but try and retain an appreciation for what you’re watching – even if it’s your player two sets and a break down in the fourth. Hell, if you’re one of those devoted Nadal fans who likes nothing more than watching Federer lose (or vice versa), cherish the sensation of watching the other guy lose. Because tennis in 2025 will be a more desolate place than you’d like to imagine.

Maybe Federer will be clutching the trophy on 15 July – one more for the road, old boy? – maybe he’ll trudge out before the quarters. Whatever the circumstances of whatever will be his final Wimbledon appearance, tears will be shed when Roger departs the stage. He’ll walk off Centre Court for the final time, arm raised in farewell, soul perhaps a little lighter, leaving behind a sport that is impossibly grateful, and unspeakably bereft.

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