Novak Djokovic sets up Roger Federer semi-final

(GETTY IMAGES)

Novak Djokovic powered into the Australian Open semi-finals after beating Tomas Berdych in straight sets tonight.

The third seed won 6-1 7-6 (7/5) 6-1 in two hours and 32 minutes to set up a semi-final clash with defending champion Roger Federer, who proved too strong for Swiss compatriot Stanislas Wawrinka earlier.

Djokovic was 4-1 down in the second set but hit back to take it to the breaker which he won to break Berdych's spirit.

The first and third were more straightforward.

Djokovic broke for a 2-1 lead early on and then again for 5-1 as the Czech struggled to find his range.

But, after saving two break points early in the second, Berdych started to fire. He established a 4-1 lead and seemed to be on his way to levelling it up.

But Djokovic hit back to cancel out the break and, with the roof now closed due to the threat of showers, it went to the breaker.

A mini-break was claimed by each player before the world number three struck again on set point.

And with that the momentum was firmly with Djokovic and he broke twice in the third to cruise through.

"In a lot of the points I was trying to change the pace because when he is in his comfort zone he is a very dangerous player," said Djokovic.

"The second set was very close and I was very lucky to win the breaker.

"It was a huge confidence boost to win that set and it meant I could go for my shots.

"I am taking one match at a time but if I continue playing like this I have a good chance.

"But in my next match I have Federer - he is the best player there has ever been - so we will see."