Karlovic's power is futile against Federer

Giant Croat's limitations are exposed as world No 2 coolly continues progress

To those who had contested – or observed, rather – 79 unbroken service games from Ivo Karlovic on his way into the last eight, it may or may not have been tennis. In the end, however, you found yourself admitting a pang of sympathy for the big man yesterday when he encountered one of the all-time tennis thoroughbreds, and was duly exposed as a one-trick pony.

Roger Federer, the seraph of the sward, ended the Croatian ogre's immaculate service run at this tournament as early as the fourth game. Afterwards, Karlovic attributed the immediacy of this breakthrough not only to Federer's "unbelievable" returns, but also to the dazzle of the sun, which he redressed with a natty pair of shades. Somehow, after losing 6-3, 7-5, 7-6 in just 103 minutes, it seemed all too fitting. Here, plainly, Icarus was flying too close to the sun.

At 6ft 10in, of course, the tallest player in ATP history takes pretty literal liberties with the ozone layer. If you want to lob Karlovic, you first need to get clearance from air traffic control. But the reality was that even Federer would seldom prolong their exchanges sufficiently to resort to such extremes.

Everyone in Centre Court knew what they were in for, their fans twitching like butterflies in the bleaching heat. Points would be nasty, brutish and short. In seeing off Jo-Wilfried Tsonga in the third round, Karlovic had detonated no fewer than 46 aces. On the other hand, Karlovic's game is otherwise so chronically lacking that his only conceivable strategy against Federer was presumably to hang in there for three tiebreaks.

Should we have felt some unease, then, about this confusion between different altitudes? Should a Grand Slam quarter-final – Karlovic's first, at the age of 30 – ever be reduced to such a freak show? Federer himself furnished the best of answers, both on and off the court. First, he proved that what divides a champion from the rest is a wholesome equilibrium of talents. His own serve, for instance, is not too shabby. Indeed, it yielded just three points through the first set. And above all there was the mental resilience so conspicuously lacking in Tsonga, who lost faith in his own, very considerable talents. Federer did not betray the faintest exasperation as he strolled along the baseline after another 138mph ace. His time would come.

Then, after the match, Federer showed dignity and respect when invited to disparage his opponent's antediluvian game. "Look, everybody plays different, you know?" he said. "I enjoy playing Ivo. It's not fair to call him boring. He's got a phenomenal serve. The way he backs it up with his volleys, it's quite something. I think it's exciting, actually, to go see him play. I thought it was an excellent match."

But while Federer had indeed been obliged to prise open his opportunities, in doing so he amply disclosed the abyss dividing the two men. On one glide, he muffled a drop shot with a delicacy so beyond his opponent's comprehension that he was walking back even as Karlovic pounded clumsily towards the ball.

As in the first set, Federer settled the second with a sequence of stabbed, instinctive returns, this time as Karlovic served at 5-6. And while Karlovic had the effrontery to force a deuce – the only one of the match – in the third set, Federer peremptorily dismissed the crisis. Both players then made perfunctory haste towards the tiebreak, but that was only ever going to go one way. Karlovic, to his credit, did not miss a first serve, but a whipped backhand on to the baseline secured Federer four match points.

Karlovic had mustered just three of his 23 aces in the first set, and missed several rudimentary volleys. Intimidation means different things to different people. Mild as he is, away from the service line, Karlovic confessed his awe afterwards. "Maybe the best player ever," he said. "But on grass he's by far the best, I think."

Federer now meets Tommy Haas, who recently took the first two sets off him at Roland Garros. How had he got himself out of that pickle? "Belief, I guess," Federer said. "I was playing well, but he was ahead. It was maybe hard to accept. But I stayed calm."

He duly extends his record sequence of Grand Slam semi-finals to 21. "Where I'm definitely good is like when it really matters, and you get maybe only a couple of chances a match," he said. "I know I will believe. The opponent knows it, too."

A man for all seasons, surfaces, situations. The very antithesis, that is to say, of his opponent yesterday. And for showing us the difference, we can be grateful to both.

Numbers game: Wham-bam tennis

13 Games were played before a rally of 15 shots or more was achieved.

27 games were played before Federer was taken to deuce in a service game.

2 Breaks were achieved in the entire match, both on Karlovic's serve.

94 per cent was the ratio of points won by Federer on his first serve.

23 aces were served by Karlovic throughout the match.

129 MPH was the average speed of Karlovic's first-serve.