United States' Serena Williams returns the ball to Spain's Carla Suarez Navarro.
The incident occurred during a practice session before the start of this year's tournament, reports Xinhua news agency.
The seven-time Wimbledon champion, playing just her sixth tournament of 2019, defeated Carla Suarez Navarro on Monday to reach the quarter-finals.
Meanwhile, Italy's Fabio Fognini was fined $3,000 for saying during his third-round loss that he wished a bomb would hit Wimbledon.
Australian Nick Kyrgios was imposed two fines, one for $3,000 from the first round and another for $5,000 from the second round, both for unsportsmanlike conduct.
He lost to Rafael Nadal in four sets in the second round.
Indo-Asian News Service
Tennis star Serena Williams has revealed that she has apologised to Japan's Naomi Osaka who defeated her in the finals of the US Open last year.
US tennis superstar Serena Williams topped Forbes magazine's list of the highest paid women in sports for the fourth straight year on Tuesday.
Serving only so-so, failing to convert all but one of her break chances and missing groundstrokes with alarming regularity, Williams stunningly exited in the third round at Melbourne Park, beaten 6-4, 6-7 (2), 7-5 by 27th-seeded Wang Qiang of China on Friday.
All eyes will be on all-rounders Ben Stokes and Jason Holder in Southampton as they will lead their respective teams on the pitch at Ageas Bowl to mark the beginning of this historic series.
International cricket returns on Wednesday following the coronavirus lockdown when England play the first match of their three-Test series against the West Indies at the Ageas Bowl in Southampton, followed by two matches at Old Trafford, in Manchester.
The manager renowned for his own flashpoints and volatility was delighted to see tensions between teammates erupting in public view.