Battling a long slump, Roger Federer angrily broke his racket en route to a 3-6, 6-2, 6-3 loss to Novak Djokovic in the Sony Ericsson Open semi-finals.

Federer fell behind 2-love in the third set, and when he netted an easy forehand to start the next game, he slammed his racket to the concrete, mangling it. The outburst was a shock coming from Federer, winner of the ATP Tour's sportsmanship award for the past five years.

The No. 3-seeded Djokovic's opponent in the final today will be No. 4 Andy Murray, who became the tournament's first British finalist by beating No. 6 Juan Martin del Potro 6-1, 5-7, 6-2. Murray improved to 56 wins against seven losses since last July.