The protester “has been arrested and the situation is being handled by the police,” Laver Cup organizers said in a statement.
Federer, a 20-time Grand Slam champion, was slated to compete hours later Friday, teaming up with longtime rival Rafael Nadal in a doubles match.
The 41-year-old Federer hasn't played an official match since Wimbledon in July 2021 and is ending his playing career after a series of operations on his right knee.
There have been other instances of high-profile tennis matches being interrupted in recent years, including during the 2009 final at Roland Roland Garros, when a man went up to Federer and tried to put a hat on his head.
At this year's French Open, in June, a protester wearing a T-shirt with the message “We have 1028 days left” interrupted the men’s semifinal between Casper Ruud and 2014 U.S. Open champion Marin Cilic by attaching herself to the net with metal wires and glue and kneeling on the court.
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