If you’ve ever watched the U.S. Open, you’ve probably marveled at the sheer number of balls that get used. Players swap them out constantly, hundreds of matches are played, and by the end of the tournament, there are enough fuzzy yellow balls to make your dog’s dreams come true. But what happens to those U.S. Open tennis balls after a tournament? As the 2026 U.S. Open returns to New York from Aug. 23 through Sept. 13, it’s the perfect time to fi…