The loss of Exum for an extended time could hurt depth at guard for the Mavs, who added former Golden State star Klay Thompson in the offseason. DALLAS — Dallas Mavericks guard Dante Exum injured his right wrist during training camp in Las Vegas, and the team gave no timetable for a return. The injury to Exum comes after star guard Luka Doncic sustained a calf injury during a workout before the Mavericks left for Las Vegas.