WATCH: Klein gets game penalty for yelling "stupid"

An ATP Challenger match between Sam Groth and Brydan Klein has gone viral for all the wrong reasons. In Nottingham, chair umpire Mohamed Lahyani made what appears to be a bewildering call, coming hot on the heels of Jerzy Janowicz being penalized in Stuttgart for allegedly saying "hamburger."

Groth was serving for the match—down break point—when Klein netted his return and yelled out: "Stupid, stupid person. Hit it."

It appears that the world No. 209 was berating himself for missing a return that could have helped get him back into the match. Lahyani thought otherwise.

The chair umpire gave Klein a game penalty after having given him a warning for ball abuse and a point penalty for unsportsmanlike conduct earlier. The game penalty ended the match in favor of the Australian, 6-3, 6-4. As you can see in the video, Klein was unhappy with Lahyani’s decision.

Klein's point penalty came at 4-5 down in the second set after disagreeing with a call a lineswoman made that would cost him his service game. He uttered a swear word near the umpire's microphone and complained, "[She's] a sixty year old lady wearing like a..." before Lahynai cuts him off.

"This is lack of respect, you don't talk like this to anyone," Lahyani said, and would repeat this phrase when he gave Klein the game penalty minutes later.

Groth advanced to his second ATP Challenger quarterfinal of the season.

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