Thursday's US Open women's semifinal between Coco Gauff and Karolina Muchova was halted in the second set after what appeared to be protesters in the crowd disrupted play in New York.
The US Open called it a "fan-related" incident, according to a statement, and said one attendee "affixed himself to the floor and due to the nature of this action, medical professionals, NYPD and security personnel were needed in order to resolve the issue and remove the fan from the stands."
As the attendee -- who was shouting about "environmental issues," according to the ESPN broadcast -- was removed, the fans on hand at Arthur Ashe Stadium cheered.
Gauff and Muchova had left the court during the pause, then returned and play eventually resumed after more than a 45-minute delay.
Four protesters were involved, and three of them "were escorted out of the stadium without further incident," according to a statement from the US Tennis Association on Thursday night.
USTA executive Stacey Allaster told the ESPN broadcast: "There's no doubt in a 24,000-seat stadium, hopefully, people don't get ideas.
"We know in these large events, environmental protestors use the platform. Certainly, security will be resuming -- along with NYPD -- to see what we can do to prevent it in the future."
After winning the semifinal, Gauff told reporters that while the delay interrupted her momentum, she is not upset about the disruption.
"I always speak about preaching ... about what you feel and what you believe in," Gauff said. "It was done in a peaceful way, so I can't get too mad at it."
"If that's what they felt they needed to do to get their voices heard, I can't really get upset at it," Gauff added.
The 19-year-old said she expected a protest may happen at some point during the tournament after similar protests earlier this year at tournaments, including anti-oil protestors at Wimbledon.
"I prefer it not to happen in my match but I wasn't pissed at the protesters. I know the stadium was because it just interrupted entertainment," Gauff said.
