The extra day puts the U.S. Open in line with the Australian Open, which switched its start from Monday to Sunday a year ago, and the French Open, which was the first tennis major to make the move when it added a 15th day in 2006.

The US Open is expanding to 15 days this year, shifting to a Sunday start for the first time in the Open era that began in 1968.

The U.S. Open tennis major will expand its main draw to 15 days in 2025, beginning on a weekend for the first time in the Open era.