Djokovic makes his chances count to reach third round

Defending champion Novak Djokovic gave rising American Ryan Harrison a lesson in control as he booked his third-round place at Wimbledon tonight.

Djokovic was never expected to lose to the 20-year-old but a stern examination was always on the cards and so it proved, even though the Serbian was a comfortable 6-4 6-4 6-4 winner.

Harrison was able to match his decorated opponent for large parts, often unleashing a stinging forehand, but when the pressure was cranked up Djokovic was the one to stand firm.

He took the three break points that came his way, while at the other end Harrison squandered six in a game when they were presented to him midway through the second set.

It was a tough lesson for Harrison to learn and the pattern was set in the first set.

He first lost his serve in the fifth game despite being the better player. He chased down a volley and hit a forehand winner before leaving Djokovic flatfooted when he pinned a cross-court one-hander beyond him.

Djokovic remained composed, though, and broke serve when Harrison got too excited and slapped a forehand long.

Djokovic served the set out and Harrison showed he had learned little from the opener as he allowed six break points to slip through his fingers. Having found a way to get on top of the Djokovic serve, he went through a range of ways to fritter chances away, ranging from a misplaced smash to some wild forehands.

As if to ward the rookie off trying to break him again, Djokovic took his serve off him in the very next game - Harrison's wayward hitting prominent again - and the set was again seen out by the world number one.

Knowing he needed something special to stir fanciful hopes of a comeback, Harrison upped the ante in the third set, serving well and restraining himself where previously he had not, but even then he was undone, losing serve in the ninth and what proved to be penultimate game.

Djokovic had three chances to put himself on the brink and needed just one, haring in on a poor drop shot, before serving out.

Djokovic acknowledged he had been given a working over by Harrison.

"It was a straight-sets win but much more difficult than the scoreline shows," he said.

"It was a great match but I was in trouble in the second set and it could have gone either way. It is difficult to adjust under the roof, and Ryan was serving fantastically."

Djokovic returned a first-serve percentage of 76 per cent and a second of 78 per cent - Texas native Harrison could only show a 43% return on his second.

"I was very pleased with my serve and performance," Djokovic added.

"I think I played really well from the start. It was a close match, he performed really well but I got the crucial breaks in every set when I needed to."