Fan ejected after 'Hitler phrase' during German 12th seed's match in US Open

A fan was ejected from the US Open after Germany's Alexander Zverev protested about a "Hitler phrase" being shouted from the stands.

Zverev was serving in the fourth set of his last 16 battle with Italy's Jannik Sinner on the Arthur Ashe Stadium when the drama unfolded on Monday.

The 12th-seeded Zverev approached chair umpire James Keothavong to complain about the alleged catcall.

"He just said the most famous Hitler phrase there is in this world," Zverev told the umpire. "This is unbelievable."

Keothavong consulted with security officials in an attempt to identify the culprit.

Eventually a man wearing a blue baseball cap was singled out and ordered to leave the arena.

The late-night US Open crowds on the 23,000-capacity Arthur Ashe Stadium are famously boisterous but have been criticised during the tournament.

Former Australian professional Rennae Stubbs said shortly after the Zverev incident on Monday that there were fans at night sessions that were "not good".

"I love the fans but at this point there are some bad characters," Stubbs wrote on X, the social media site formerly known as Twitter.

"I had a drink thrown on me last night by a drunk fan who was fighting with her boyfriend. Now we got someone yelling Hitler slurs! Wtf? Come on peeps."

German player Laura Siegemund also vented at the Arthur Ashe crowd after her first round defeat to Coco Gauff last week.

"They had no respect for me, no respect for the way I played, no respect for the player that I am, they had no respect for good tennis," a tearful Siegemund said.