MIAMI, (Reuters) – An out-of-sorts Roger Federer  smashed his racket in frustration as he fell to a 3-6 6-2 6-3  defeat to Serbia’s Novak Djokovic in the semi-final of the Sony  Ericsson Open yesterday.

Djokovic, ranked third, will now play the winner of the  second semi between Britain’s Andy Murray and Argentine Juan  Martin Del Potro in tomorrow’s final.

After Del Potro eliminated Rafael Nadal Thursday, the Miami  crowd backed Federer in the hope of seeing one of the world’s  two best players in Sunday’s final.

But Federer, who made 47 unforced errors, did not look like  the man who dominated the sport for so long.

After winning the first set comfortably against an  error-prone Djokovic in just 25 minutes, Federer faded badly in  the second.

In windy conditions, the Swiss won just 57 percent of first  serve points in the second and it got worse in the third as  Djokovic broke at the first attempt.

Down 30-0 in the third game of the final set, Federer played  a forehand long and responded by hurling his racket to the  ground, totally disfiguring it and drawing jeers from the crowd.

Four years ago at the same venue, Federer was down two sets  to Nadal when he smashed his racket and then came back to win in  a five-set thriller in the final.

This time, although Federer got the crowd going and won two  games in a row from 4-0 down, Djokovic kept his cool to secure  just his third win in 10 attempts against Federer.

Federer blamed the conditions for a large part of his loss.

“I thought I was playing okay in the first set but it was  always going to be tough in the wind,” he told reporters.

“I already felt it in the warm up. It was coming across the  court. I struggled heavily. It was tough.”

The Swiss said he also had the sun in his eyes during the  ball toss.

“It’s the same thing for both players. Once one guy gets the  upper hand, the other guy is a bit uncertain. It’s tough but he  struggled big time in the first set,” said the second seed.

“I finished worse than him. He played so bad in the first  set, I had a great effort by finishing even worse than him.”

Djokovic was pleased by the way he kept his composure once  he had got the upper hand.

“He just wasn’t playing anything really special.  He was  just playing really wisely and changing the pace and playing a  lot of short slices on my backhand.

“That’s where he opened up the opportunity to make offensive  shots. That’s what it did. Afterwards, I was the one who was  changing a lot of pace and I was playing a lot of spins and just  waiting patiently,” he said.