Reilly Opelka slams umpire after controversial win over Cameron Norrie in Dallas

After coming from a set down to take the last-16 encounter to a decider, Opelka found himself serving for the match at 4-6, 7-6 (7-5), 5-4 when the drama unfolded.

A fan had been heckling throughout the match, but the world No 145 finally had enough with the score 5-4 (30-30).

"Are you doing it on [expletive] purpose or what?! Go the [expletive] inside, buddy," the American told the fan.

The heckler was eventually removed, but it cost Opelka on the scoreboard as Allensworth gave him a code violation and a point penalty, which meant Norrie was now 30-40 up.

Opelka managed to avoid the break and he eventually sealed the win on his first match point, but he was furious with the official and made his opinions known during an interview with journalist Cheryl Murray.

"Greg Allensworth is the worst ref [umpire] in the ATP. We were talking about him in the locker room, all the players, it really is a coincidence about two days ago [we were talking about the worst umpire on the tour and he] is the worst one ⦠Allensworth is real bad, he almost changed the outcome of that match, just because he doesn't really know what he is doing," he stated.

"He got emotional, he got very tense and frantic and he couldn't give me an answer. He didn't tell that guy to shut up. He [the heckler] was doing it for three points, he didn't do his job so I had to tell him 'get out of here', the guy was being quite rude.

"I am all for whatever, but if you want to come here to be an a*****e then I am going to be one back. It shouldn't be one-sided traffic, if you want to be disrespectful to me, I can't just be a punching bag and if the ref isn't doing his job and he penalises me it is not a good look.

"It almost changed the outcome of the match, big point, he didn't do his job and then penalised me for it so he did two things wrong.

"I hope the ATP penalise him, maybe sideline him for a few tournaments."

Unsurprisingly, there was no handshake between Opelka and Allensworth after the match.

Opelka, who is set to rise to No 125 in the ATP Rankings after his win, will face fellow American Tommy Paul in the quarter-final.

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