James Lawton: Novak Djokovic is the warrior as others go by wayside

Nobody set to replace Big Four, with Dimitrov more famous for his girlfriend and Raonic without a significant Grand Slam performance

Power vacuum: Novak Djokovic en route to beating Jérémy Chardy in straight sets last night after other titans fell and were not replaced (EPA)

At any other Wimbledon bathed in evening sunshine it might have been a passing observation but here last night, after the days of mayhem which have left the greatest generation tennis has ever known with two of its towering forces departed, it sounded more like a reproach.

"Look, there's Grigor Dimitrov," said the celebrity-spotter. "He's Maria Sharapova's boyfriend, you know."

It was for some years not quite the graduation that big-time tennis had in mind for the 22-year-old Bulgarian who this week trailed out of the action he was supposed to increasingly influence, a five-set second round loser to the obscure Slovenian Grega Zemlja.

Dimitrov, along with the huge-hitting Canadian Milos Raonic, was supposed to be the next big thing, a kid with superb talent and instinctive feel for the game who was surely destined to challenge the Big Four of Roger Federer, Rafa Nadal, Novak Djokovic and Andy Murray.

But the truth is that he collected more nicknames than significant titles. They called him "Prime Time" and, the most daunting one of all, "Baby Fed".

In the wake of the shocking departures of Federer and Nadal, whose joint absence in the second week of the tournament has left Centre Court inhabited by ghosts, a new generation has failed to materialise. Of course there are still names of worth, the dogged Spaniard David Ferrer and the estimable Czech Thomas Berdych. But you could trawl the tennis courts of the world today and you would find no authentic bearer of the nickname Baby Fed – no surefire candidate to extend the golden age.

Bernard Tomic, a teenaged Australian of Eastern European origin, sent up a flare here two years ago when he fought his way through to the quarter-finals, a rare teenage presence to recall the precocious brilliance of a Boris Becker or a John McEnroe. Tomic progressed against the knowing Richard Gasquet yesterday but it was a triumph unaccompanied by any roll of drums.

Dimitrov languishes at 31st in the world rankings, Raonic's power serving has earned him 15th place but one unmarked by even a brush with significant Grand Slam performance.

It means, perhaps more than anything, that tennis is obliged to live not for a gilded future but the enduring days of the age when Federer and Nadal defined both the power and the grace of the game – and never more spectacularly than in the final here five years ago – and were then joined by the two men who last night were providing the tournament with the last of its authentic grandeur.

The achievement of Djokovic and Murray, whatever happens in the next few days, has been to add lustre to the epoch which has surely pushed the game into uncharted regions.

Inevitably, though, there must be a sense that what happened this week was something that in some ways had already been delayed.

When Nadal fell to an unknown Belgian, two days before Federer met the same fate at the hands of an obscure Ukrainian, he was scrupulous about handing great credit to his conqueror. He said that he had played badly but he could take nothing away from the performance that had put him down.

In another 24 hours his uncle and trainer Tony Nadal said what the rest of the game already knew. He too had followed the party line that Steve Darcis from Liège had created a remarkable ambush. In what seemed like an unguarded stream of consciousness, he admitted that Nadal's health had plummeted after Paris and another French Open title, and that there was little preparation for Wimbledon.

Federer, who will soon be 32, left with a familiar story on his lips. He was shocked by defeat but he would be back next year – and still convinced of his ability to invade the imagination of the tennis world with another victory.

You have to listen to such a statement from Federer because he has confounded the logic of time and circumstance often enough, but in the bones there is another truth and it says that, by the highest of calculations, his time is surely done. This means, of course, that two men stand between Wimbledon and the appalling sense of a lost kingdom of the tennis sun.

Djokovic went on the Centre Court last night as a man anointed as arguably the most perfectly equipped tennis player of all time. When so much was falling about him like shattered masonry, Djokovic was alternatively heart-warming and chilling in the scale of his talent and level of his ambition.

And then, of course, there is Murray, who was supposed be the foundling among the tennis titans born to dominate their game. Born at the wrong time, gifted hugely but perhaps quite sufficiently, Murray was destined to lurk on the boundaries of greatness, enriching the arena but never dominating it.

Yet on the Centre Court on Friday night, when he stripped down Tommy Robredo in three sets of the easiest accomplishment, he never seemed more at home. He had long passed the time when he might be described as anyone's boyfriend, but now there is a very good chance he might just become the head of the tennis household.

Given his competitive maturity, no one can claim – even after such a week – that it is too severely diminished.