Federer and Roddick through as Djokovic drops out

(GETTY IMAGES)

World number two Roger Federer set up an Australian Open semi-final showdown with American Andy Roddick after he demolished Argentine Juan Martin del Potro 6-3 6-0 6-0 in the quarter-finals.

Two days after Federer was surprisingly taken to five sets by Tomas Berdych, the 13-times grand slam winner wasted little time in thrashing the eighth seed in just 80 minutes.

The 20-year-old del Potro, considered to be one of the rising players of the game having won four tournaments last year and the Auckland event earlier this month, had no answer to the Swiss.

Such was Federer's dominance, del Potro won just eight points in the second set and six in the third as the 27-year-old Federer advanced to his 19th successive grand slam semi-final.

Meanwhile, Novak Djokovic and Andy Roddick both raised concerns about the scheduling of matches following the Serbian's retirement in their quarter-final at the Australian Open.

The defending champion retired early in the fourth set trailing 6-7 (3/7) 6-4 6-2 2-1 after struggling in the intense heat on Rod Laver Arena, handing Roddick a place in the semi-finals for the fourth time at Melbourne Park.

Djokovic's previous match against Marcos Baghdatis on Sunday night ran into the early hours of yesterday morning and the third seed revealed after today's game he had requested to play a night match but had been turned down.

"It doesn't benefit a lot of people to play that late. But on the other hand, if you end a match at 3am it's basically logical thinking that you should play the same match, the second match after 7.30pm (in your next round)," Djokovic said

When asked why his request had been turned down, Djokovic replied: "Sometimes you don't have enough power obviously to get things right for yourself.

"It was probably, I don't know, TV or things like that; some requests, other requests, which is, you know, a little bit disappointing. But what can you do?

"It's on the tournament organisers to decide whether they are going put me or her (Dokic), or whoever plays, on prime time," Djokovic added.

"I don't blame them putting an Australian on at 7.30pm. Obviously, it attracts most people and attention.

"You have got to think about people, about the public, about everybody. That's what it's all about. You can't think only about the players.

"But sometimes you have got to hear what the players have to say. Things like this (retirement) don't happen for no reason."

Having had to overcome similar circumstances at the US Open, Roddick had some sympathy for his opponent and suggested the early night match should not just be the domain of the women.

The 26-year-old American said: "My only suggestion would be - and hopefully this will be well received - if everything is equal all across the way, I feel like maybe the men should get the first (night) match every once in a while during the first week of a slam.

"If all things are equal, then I feel like the scheduling should be the same."

The first sign that Djokovic was struggling came in the third set. With the match all square at one-set each and the Serbian leading 2-1, he called for a medical time-out and had treatment for cramp and the heat.

When he returned from the extended break, he lost the next five games and the third set 6-2.

Although he came out in the fourth set, it was clear he was struggling and, having dug deep to hold his serve in the opening game, was broken in the third and informed the umpire he could no longer continue.