PARIS • Novak Djokovic extended his win streak to 20 at the Paris Masters on Friday, defeating Tomas Berdych 7-6 (7-3), 7-6 (10-8) to reach the semi-finals. But Rafael Nadal lost to Stan Wawrinka.

World No. 1 Djokovic has now won 28 sets in a row, dating back to the US Open final in September.

But he had a battle on his hands against Berdych. Neither player could manage a break of serve, the first time that has happened to Djokovic in 680 career wins.

"It was decided in tiebreaks two times, and very few points decided a winner today," said Djokovic.

Berdych had the better of the first set and his chance came with a set point at 6-5 up.

But Djokovic produced a big first serve and a forehand winner off the blocked return.

The tie-break, however, was dominated by the Serb winning four of the first five points to take control. Serves again dominated in the second set with both men holding firm to bring up a second straight tie-break which Djokovic edged 10-8.

Djokovic was yesterday set to play Wawrinka, who ended a tense encounter with Nadal by saving two set points in the second set, winning 7-6 (10-8), 7-6 (9-7).

AGENCE FRANCE-PRESSE, REUTERS

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