Reilly Opelka faces potential discipline for his post-match comments about a chair umpire he called the “worst ump on tour,” the ATP said in a statement Friday. Opelka was angered that he received a point penalty while serving for the match in the third set against Cameron Norrie at the Dallas Open on Thursday night.

Opelka criticized the umpire after he was penalized for twice swearing at a spectator, describing him as 'amateur hour' and 'bush league.'

Reilly Opelka's win over Cameron Norrie at the Dallas Open ended in controversial fashion and the American didn't hold back in his criticism of chair umpire Greg Allensworth after the match.

Reilly Opelka has called for chair umpire Greg Allensworth to be suspended by the ATP after he received a code violation at the Dallas Open for confronting a spectator in the stands who he claimed was deliberately coughing to interrupt his serve.

The 211cm American let rip at the chair umpire over his lack of action against a fan heckling him from the stands.