Djokovic fends off Muller to reach quarter-finals

Djokovic was pushed by the 42nd-ranked Muller, a big-serving left-hander with the shots to rally with the top seed, but the four-times champion was almost bullet-proof on serve and cut the 31-year-old down repeatedly when he rushed to the net.

It wasn't until the sixth game of the third set that Muller had a chance on the Serb's serve but the former junior world number one could not take it despite four break points.

Djokovic struck a string of sumptuous winners to break Muller in the 11th game of the third set and served out the final game to love to book a quarter-final clash with Canadian eighth seed Milos Raonic.