Alize Cornet received a code violation for changing her shirt on court ©Getty Images

The US Open says it "regrets" that Alize Cornet received a code violation for changing her shirt on court at the tennis Grand Slam.

A sexism row has broken out after the incident at New York's Flushing Meadows yesterday.

France's Cornet left the court to change her shirt between the second and third sets during her first round defeat to Sweden's Johanna Larsson.

On returning she realised that it was back-to-front and quickly corrected her mistake at the back of the court.

It happened during intense heat but Cornet was given a warning by the chair umpire.

Many, however, have pointed out that male players can change shirts on court with no consequences.

Organisers the United States Tennis Association attempted to clarify their position.

"We regret that a code violation was issued to Ms Cornet," it reads.

"We have clarified the policy to ensure this will not happen moving forward. 

"Fortunately, she was only assessed a warning with no further penalty or fine.

"Female players, if they choose, may also change their shirts in a more private location close to the court, when available. 

"They will not be assessed a bathroom break in this circumstance."

Former Australian player Casey Dellacqua called the warning "ridiculous" while Judy Murray, mother of Britain's double Wimbledon and double Olympic champion Andy, was also critical.

Larsson won the match 4-6, 6-3, 6-2.