Novak Djokovic plays through hamstring injury to beat Grigor Dimitrov at Australian Open

The title favourite again appeared to struggle with his leg but secured a straight-sets victory

Novak Djokovic had more treatment to his left leg (Aaron Favila/AP) (AP)

Novak Djokovic continued to defy a hamstring injury as a straight-sets victory over Grigor Dimitrov sent him into the fourth round of the Australian Open.

The title favourite admitted after needing a medical timeout and dropping a set to French qualifier Enzo Couacaud that he was concerned, and a clash with 27th seed Dimitrov was a much better test of his physical condition.

He took another timeout after falling to the floor at the side of the court at the end of the first set but, despite continuing to limp and looking uncomfortable at times, clinched a 7-6 (7) 6-3 6-4 victory.

It was only two years ago that Djokovic tore an abdominal muscle during the tournament yet still managed to win a ninth title, and none of his rivals will be expecting him to give up the chance of a 10th without an almighty battle.

The strapping on Djokovic’s left leg was even more substantial than on previous days but he settled well into the match, breaking serve in the opening game.

Dimitrov saved three set points at 5-3 and it appeared Djokovic was in full control but he was broken serving for the set and then had to save two set points, one at 5-6 and one in the tie-break.

When he took the set with a volley, the crowd would have expected to see a celebration, but instead Djokovic collapsed to the court looking stony-faced and called for the trainer.

The pain was evident on his face as he had the muscle massaged but, although there were moments when Djokovic did not appear to be moving properly, particularly going forwards, he was able to hare around on the baseline seemingly without too much hindrance.

Having beaten Dimitrov nine times in their previous 10 meetings probably helped. The Bulgarian at times threatened to make things complicated for Djokovic but, despite going down on the court twice more, he found a way through to set up a clash with Australia’s Alex De Minaur.