Novak Djokovic sets up first-ever duel on grass with Roger Federer

Djokovic reached the semi-finals with a straight sets victory (Getty Images)

Now for a real challenge. Beaten only once in his last 33 matches – by Rafael Nadal at Roland Garros – and dropping a single set here, Novak Djokovic will stand across the net tomorrow in the semi-finals from a man he calls "probably the best player in history", Roger Federer. Yet such is his own form that, as world No 1 and top seed, the Serb will start as deserved favourite.

In yesterday's Court One quarter-final he dismissed Germany's Florian Mayer, the lowest remaining seed, by 6-4, 6-1, 6-4. Any encouragement offered to Federer by a slow start and 20 unforced errors could be explained away, he suggested, by having to adapt from playing his previous three matches under the Centre Court roof.

There was also one of those brief rain breaks that just about offer time to return to the locker room before coming out again, and then the strange appearance of a warm yellow thing in the sky. "I had a little trouble adjusting, you know, to the sun and to outdoor conditions because I played last three matches indoors," he said. "So it took me a bit of time to get into the rhythm."

While he was doing so, the lanky Mayer had an opportunity he will rue for the rest of his career. Having boosted his confidence with an early break, and then immediately been pegged back to 3-3, he came out after the rain break to take a 40-0 lead on the Djokovic serve but failed to convert any of the three chances. Opportunity had knocked, then gone away again without receiving an answer, and Mayer's fear that it would not come back turned out to be fully justified.

He dropped his serve in the next game and with it the first set, and was comprehensively outplayed in a second set lasting only 25 minutes.

"To be honest, the first set I have to win," Mayer admitted. "I was break up. Then it was 4-4, 0-40, easy volley and I let him come back. Then I lost my service game after 40-15. That shouldn't happen. But after the first set, he played unbelievable, especially in the second set. He showed why he's the best player right now in the world."

Mayer, who went through a bad time psychologically four years ago after dropping out of the top 300 following injury, is a strange mixture. Almost beaten twice in earlier rounds, he played what he called a "perfect match" in knocking out Richard Gasquet, the 18th seed, on Tuesday, but is capable of the sublime and the ridiculous on successive points. That was evident in the fourth game of the second set when he won applause from Djokovic for an acrobatic winner at the net, only to drive long on the next point and drop his serve.

Djokovic sealed that set with one of his seven aces and the match with another, although Federer will have noted one or two loose games in between. "If I could win the first set maybe I have a small chance," Mayer said. "But still it's very, very tough to beat him. It's not impossible, but if you don't take the chances you get, like in the first set, you cannot beat the world No 1."

What chance of Federer doing so then? "It's a very open match. I think it's a good chance also for Roger maybe to reach world No 1 if he can beat Novak [and win the final]. So he will be very motivated. But I think Roger also has to play on a really high level to have a chance."

Djokovic said of the task: "Roger has great variety in his game. He uses his serve very well. He opens up the court. He uses that slice really well to get the balls to bounce low. He's very aggressive at times but he can defend well. I think that grass courts are suiting his style of game the most, so it's going to be an interesting match."

The Serb did not mention that he has won six of the last seven meetings between them. Federer retains an overall head-to-head lead of 14-12 but, just to add to the intrigue surrounding this semi-final, they have never met at Wimbledon – or, indeed, anywhere else on grass.