According to the official team twitter, Singleton is missing Saturday's tilt against the Cleveland Cavaliers at Quicken Loans Arena with a right shoulder contusion. For now, there's no timetable on when Singleton will return to action.
Singleton showed some promise in his rookie campaign last year, averaging 4.6 points per game and earning 51 starts.
Unfortunately for Washington, it also watched Seraphin leave the game with what's being deemed a strained right calf, per Michael Lee. The third-year man is currently questionable to return.
It's been a rough offseason for the Wizards, who have already seen their star point guard John Wall succumb to a stress injury in his left knee. If his recovery goes according to plan, Wall will only miss the first couple weeks of the regular season.
The 2012-13 Wizards season starts Oct. 30 on the road against the Cavaliers.