The American tennis star didn’t hold back during and after the contest.

Reilly Opelka hit out at the umpire during his match against Cameron Norrie (Image: Getty)

Tennis ace Reilly Opelka could be hit with a hefty punishment after claiming one umpire was the “worst ump on tour”.

Opelka was taking on Cameron Norrie in the second round of the Dallas Open earlier this month – a match the American went on to win 4-6, 7-6 (5), 6-4.

But it was an eventful contest nonetheless, with Opelka penalised for using a profanity towards a member of the crowd, after claims the supporter was repeatedly interrupting his serve.

Confronting the fan, he asked: “You doing it on f***ing purpose or what?” Prior to telling them to get out.”

After the match, Opelka didn’t hold back on his assessment of the incident, particularly in relation to chair umpire Greg Allensworth, with the 27-year-old stating: “Worst ump on tour. He’s real bad.

“Almost changed the outcome of that match just because he doesn’t really know what he’s doing.

“And he got emotional, when we were arguing. … He didn’t tell [the fan] to shut up? He was doing it for, like, three points. He didn’t do his job, so I had to tell him, ‘Get out of here.’”

Reilly Opelka defeated Cameron Norrie in the second round (Image: Getty)

As a result of his outburst, the ATP have taken action against Opelka, with a statement reading: “Audible obscenities directed at members of the public constitute a clear violation of ATP rules.

“In such instances, the chair umpire has a responsibility to take appropriate action, regardless of the match score. The ATP will review Mr. Opelka’s post-match comments as part of its standard disciplinary process.”

On Allensworth’s performance, Opelka added: “He gets no penalty. If I lose that point, I lose that match, that’s a difference in my paycheck. He gets no repercussions. That was bush league.

“The guy shouldn’t have a job or should be sidelined for about four weeks and you learn a thing or two. You can’t make those calls in ATP 500s. You’ve got to understand the situation. You can’t always play by the rulebook. It’s common sense.”

After beating the British No.2, Opelka went on to lose 7-6 (7-3), 6-2 to Tommy Paul in the quarter-final of the event.

He’s back in action on Monday though, facing Christopher Eubanks at the Delray Beach Open in Florida.