Novak Djokovic said he was unhappy with his performance despite a 17th consecutive win at Grand Slams at Wimbledon.
Djokovic beat Dennis Kudla in straight sets on Friday to power into the second week of the competition.
The 6-4, 6-3, 7-6 score suggested a routine win for the Serbian star, but he says he sees plenty of room for improvement.
“We were pretty even up until the finish of the first set,” Djokovic said after the match.
“I am not too pleased with the way I performed, especially with the serve. I had to slow the pace down and mix it up because he has a flat ball.”
Djokovic attracted criticism for some of his interactions with the Wimbledon crowd, with him appearing to direct an aggressive roar at those vocally supporting his opponent on Court One.
However, he has downplayed the incident saying there is nothing more to it than a simple release of pressure.
“In the heat of the battle, those things happen, you release the emotions, the stress, the pressure you feel on the court,” he admitted.
“Sometimes you are looking for some support and sometimes you just want to let [your emotions] go – and that’s what happened for me.”
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