Novak Djokovic has issued another damning assessment of the quality of surfaces at Wimbledon in 2017, describing the courts as "not that great" after pointing out a hole on Centre Court.

The Serbian summoned the chair umpire to take note of a threat to footing during his straight-sets victory over Adrian Mannarino in the fourth round on Tuesday.

A heat wave during the lead-up to the tournament, which persisted during the early rounds, has left organisers struggling to preserve the quality of the grass in SW19.

And while he acknowledged the challenge conditions have posed, Djokovic, a three-time singles champion at the All England Club, has made no attempt to disguise his displeasure at being presented with a sub-par stage on which to perform.   

"During the match I mentioned there is a hole in the middle of the court near the service line," he told the BBC.

"He [the umpire] just asked me to show him and I did and he was not very pleased to see that. 

"Courts, honestly, are not that great this year. Many players feel the same. It is what it is. 

"The weather also affects the grass. The grass-court groundsmen, they know their job the best in the world. 

"But the grass is probably the most complex surface to make, to maintain. It's not easy, they are trying their best. But I've played on better courts."

Djokovic's reward for dispatching Mannarino is a quarter-final against Tomas Berdych, who registered one of only two victories over the former world number one in 27 career meetings in the last four at Wimbledon in 2010.

"That year he beat me in [the] semis I think," Djokovic said.

"This is one of his most preferred surfaces. He likes to play on grass. He's been around for many years, Tomas is an established top-10 player. 

"[He] understands and knows exactly the occasion of playing big matches. Matches are getting tougher and tougher. There are no clear favourites anymore."