Roger Federer sails into Australian Open semis

Federer has not dropped a set at Melbourne Park and the overwhelming tournament favourite will face surprise package Hyeon Chung in the last four.

Roger Federer sailed into the Australian semifinal after beating Tomas Berdych in straight sets.

Defending champion Roger Federer recovered from a slow start to reach the semifinals of the Australian Open with a straight-sets victory over Tomas Berdych.

The second seed struggled to get going on Rod Laver Arena but fought back from a break down and saved two set points in the opener before going on to win 7-6 (7-1), 6-3, 6-4. Federer has not dropped a set at Melbourne Park and the overwhelming tournament favourite will face surprise package Hyeon Chung in the last four.

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After such an encouraging start, it was an all-too-familiar story for Berdych, the 19th seed suffering a ninth successive defeat against the domineering 19-time grand slam champion.

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The imperious Swiss struck 61 winners and broke four times to stay on course for a sixth Australian Open title. Berdych made an imposing start, Federer looking uncharacteristically out of sorts and going a break down at 2-0 after drilling a backhand wide.

The Czech timed the ball superbly for the majority of the opening set, but Federer broke back with an exquisite backhand winner after being left disgruntled when a Hawk-Eye replay failed to appear on the screen and his challenge was unsuccessful.

Federer had saved a set point to get back on serve at 5-4 and fended off another before bossing a tie-break, the 36-year-old's serve, slick movement and clean striking giving him the edge. Berdych was presented with the first break-point opportunity of the second set when Federer netted another backhand, but the world number two got himself out of trouble and combined great defence with classy groundstrokes to go a break up at 5-3.

The world number 20 appeared to be moving without any problems despite going off court for treatment with stiffness in his back after the second set, but a stray backhand had him a break down and teetering early in the third.

A blistering forehand return enabled Berdych to break straight back and level at 2-2, but another backhand winner from Federer in the next game edged him back in front, and the Swiss made the advantage stick on this occasion to wrap up a convincing win.