Casper Ruud pulled out of the US Open due to a back injury. The Norwegian was seeded at Flushing Meadows and represented one of the tournament's top draws, but the injury forced his withdrawal before competition began. Ruud has dealt with back issues before, and this latest problem sidelines him from one of tennis's four majors at a critical point in the season. His absence opens up his draw for other contenders and removes a genuine threat from the title picture.