Defending champion Novak Djokovic is well aware that he will face a major challenge in the third round of Wimbledon, when he takes on 2011 quarter-finalist Bernard Tomic.

Djokovic, 2.25 to retain his title at SW19, was rarely troubled in round two by Jarkko Nieminen, but he is expecting a much greater threat from big-hitting Australian Tomic.

“I expect him to serve well and I do expect him to mix up the game, come up with a lot of variety. That’s what he does,” Djokovic said.

“He can play flat shots. He can play short slice, come to the net. He has a very quick motion for the serve. It’s very difficult to read it on grass.

“This is the surface that he loves playing the most on, so it’s going to be a difficult match.”

Djokovic has won each of the previous three meetings between the two players, which included ending Tomic’s fine run to the last eight at Wimbledon four years ago, with the Serb prevailing in four sets.

And Djokovic’s practice partner, Tomic, is clearly in the right frame of mind to try and spring a massive upset and get off the mark against the world number one.

The Aussie said after defeating Pierre-Hugues Herbert in straight sets: “He’s number one, he’s obviously there for a reason. What a player he is.

“But, you know, I know at my level, if I’m playing good on my day, I can beat him.”

Having made the last eight four years ago, Tomic has since suffered losses in the first round, the fourth round and the second round in the last three years, with his 2011 Wimbledon run remaining his best performance at a Grand Slam.