Fans have voiced their opinions on the tense moment between Danielle Collins and Maria Sakkari in their match at the National Bank Canadian Open (Omnium Banque Nationale) in Montreal.

The heated argument came during the Round of 32 at the WTA 1000 event, a match which Collins ultimately won against the eighth seed 6-4, 6-2.

Collins had claimed the first set and was leading the second set 2-1 when the incident occurred. Sakkari's serve was called fault, but Collins hit the ball back at her opponent at the same time. This led the Greek player to rage-hit the ball outside the court, which subsequently bounced up into the crowd.

Following no reaction from the umpire Collins asked them if they had seen the ball go into the crowd.

"Did you just see that? Did you see what happened?" she said.

Sakkari did not respond well to this, telling her opponent that the ball had not hit anyone.

"It didn't even hit anyone. It was on the ground," she replied.

It was then that Collins lost her temper a little, saying to Sakkari:

"Shut your mouth. Shut your mouth."

Sakkari continued:

"What is your problem? I didn't hit anyone. I framed the ball."

At this point, Collins replied saying:

"You hit the ball into the stands Maria, you almost hit someone."

After seeing videos of the argument on social media, fans have shared their divided opinions. Some have been critical of Sakkari's actions.

"it was a wreckless hit of the ball that could have caused harm to a fan. i agree that should have been a code violation," wrote one.

However, others have also criticized the way Collins spoke to her opponent, with many taking issue with her telling Sakkari to shut her mouth.

"I would’ve lost my sh*t if someone told me to shut my mouth in a professional setting. i once quit a job on the spot because the manager told me to shut my mouth. just hung up my apron and handed over the keys and left," commented one.

"wrong behavior from both. Maria shouldn’t have done that but why collins is speaking like that?? Thank god Maria didn’t react to her “shut your mouth," added another.