Second seed Novak Djokovic looked fired up and on form as he beat Latvia's Ernests Gulbis in straight sets to reach the fourth round at Wimbledon. The three-time champion from Serbia won 6-4 6-1 7-6 (7-2), reeling off nine games in a row at one stage.

He goes on to face Adrian Mannarino, who beat fellow Frenchman and 15th seed Gael Monfils 7-6 (7-3) 4-6 5-7 6-3 6-2. Seven-time champion Roger Federer plays German 27th seed Mischa Zverev in Saturday's final match on Centre Court.

An early argument with the umpire seemed to fire up Djokovic, who told the official to "focus" and then appeared to take his own advice. From a break of serve down at 4-2 he powered into a 6-4 5-0 lead and had a set point for 10 straight games.

Gulbis, 28, clung on briefly but the second set soon disappeared and the Latvian then had lengthy treatment on his back. Ranked down at 548 after a succession of injuries, the former world number 10 recovered sufficiently to earn a break point at the start of the third set. Djokovic, a friend of Gulbis since their junior academy days in Germany, snuffed out the danger but required a tie-break to eventually see off the Latvian after two hours and 12 minutes.

Courtesy:BBC