Novak Djokovic made a swift apology to a ballgirl after she was visibly shaken when the Serb roared at her during a tense fourth-round win at Wimbledon.

Djokovic, the defending champion, trailed 3-2 in the final set with the sixth game evenly poised at 30-30 when he screamed in the girl’s direction.

• Dawn Fraser ‘sorry’ for ‘go home’, dubbed racist
• Kyrgios denies tanking in explosive press conference
• Kyrgios’ bizarre social media support spreads the love

“I’m sorry. There was nothing towards her. Maybe she was just afraid of my screaming there,” said Djokovic, who claimed he was simply trying to fire himself up in the fifth-set decider.

“I was pretty close to her. I’m definitely going to try to apologise to her if I did something wrong.”

Watch Djokovic’s scream below

In April, the Serbian superstar took to Facebook to post a video apology to a ballboy after the youngster got caught in the crossfire of a tirade at his support team during his win over Andy Murray in the Miami Masters final.

During the rant, Djokovic snatched a towel from the ballboy before the umpire gave the top seed a code violation.

While there were no official warnings on Tuesday, there was no less anxiety for Djokovic, who had to survive a nerve-wracking one-set shootout to deny the big-serving Anderson 6-7 (6-8) 6-7 (6-8) 6-1 6-4 7-5 after the match was suspended overnight at two sets all because of fading light.

“Obviously the fifth set today was very frustrating, very tense,” Djokovic said.

It was the only men’s singles clash at Wimbledon on Tuesday, with the women taking centre stage as top seed Serena Williams came from a set down to defeat Victoria Azarenka.

Maria Sharapova also needed three sets to book her spot in the semi-finals – where she will face Williams.

Spain’s Garbine Muguruza and Poland’s Agnieszka Radwanska also won on Tuesday, setting up a last-four clash against each other.