Alexander Zverev of Germany gestures to a heckler who was later removed from the match on day eight of the 2023 U.S. Open tennis tournament at USTA Billie Jean King National Tennis Center. Danielle Parhizkaran-USA TODAY Sports

A fan was ejected from his seat during the U.S. Open fourth-round match between Alexander Zverev and Jannik Sinner at Arthur Ashe Stadium in Flushing Meadows on Monday night for something he allegedly said.

Zverev was down 0-15 and getting ready to serve at 2-2 in the fourth set when he paused and approached chair umpire James Keothavong. Zverev, who is from Germany, said he heard a Hitler remark from a fan in the crowd.

“He just said the most famous Hitler phrase that there is in this world,” Zverev told Keothavong. “It’s not acceptable. This is unbelievable.”

Keothavong turned around immediately and started interrogating the fans in the crowd, demanding to know who said the alleged remark.

Eventually, the fan who said the alleged remark was identified and told to leave his seat.

Zverev did not explicitly state what exactly he heard the fan say. As a German, Zverev is extremely sensitive to the holocaust and atrocities perpetrated by Hitler and did not want a fan to get away with saying whatever was uttered. He also did not want to be caught repeating the phrase himself and deferred to the umpire to handle matters.

Zverev was leading two sets to one at that point in the match.

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