A spectator was forced to apologize to Stefanos Tsitsipas after he confronted her for imitating a bee in a bizarre incident during his match at the Cincinnati Masters.

The world number four was preparing to serve when he heard an irritating buzzing sound near him.

He then comically attempted to swat away what he thought was a bee, before composing himself to serve once again.

Frustrated, he then paused once again, before realizing the unusual noise was coming from an off-putting person in the crowd.

He proceeded to walk to the middle of the court and said to the umpire: 'There's a person imitating a bee behind me. It's a buzz right before I serve.

'Do you think that's OK?'

The umpire assured Tsitsipas he would deal with the issue, but the Greek star elected to take matters into his own hands by heading for the area of the crowd where he had heard the buzzing. 

He asked who it was that was making the noise - with one spectator pointing directly to a woman in the front row.

The world number four - who was one set up at the time - went back to the umpire - who asked if he knew who it was.

A bemused Tsitsipas then replied: 'It has never happened in my career. I know they're supporting the [other player].'

His American opponent Ben Shelton came to the net and said: 'What's happened? Are they speaking to you?'

Tsitsipas explained: 'No, they're imitating a bee, they're buzzing "bzzz".'

Turning back to the umpire, he said: 'It's the lady over there. I want her out. She needs to go.'

The umpire then reassured Tsitsipas he would diffuse the situation by asking the lady to stop.

Bizarrely, the woman then appeared to apologize profusely, raising her hand a number of times after she was approached by the 25-year-old. 

Tsitsipas went on to beat crowd favorite Shelton 7-6 (7-3) 7-6 (7-2), progressing through to the last 16 of the Cincinnati Masters where he will face Hubert Hurkacz on Thursday.

It follows a similar incident at the 2023 Australian Open, when Novak Djokovic called for a loudmouth tennis fan to be kicked out of the Rod Laver Arena after he received constant heckles during his second round match.

Djokovic told the umpire that the spectator was trying to 'get inside my head' throughout the tie-break.

'The guy's drunk out of his mind, from the first point he's been provoking me,' he said. 'He's not here to watch tennis. He just wants to get in my head.'

Djokovic also asked the umpire: 'What are you going to do about it? Why don't you get security to get him out of the stadium?'

A security official was then seen speaking to a group of fans dressed as Where's Wally to try to calm things down.

But the hecklers did not distract Djokovic, who would go on to win the title, as he incidentally defeated Tsitsipas in straight sets for his 22nd major crown.