Spurs forward Richard Jefferson could miss the start of training camp after dislocating his right thumb. Jefferson was injured Tuesday while working out at the Spurs' practice facility. X-rays were negative, and the 29-year-old swingman is expected to be re-examined next week. The Spurs called the injury minor. Training camp begins Sept. 29. Jefferson was the marquee addition in a busy offseason for San Antonio, coming to the Spurs in a four-player deal with Milwaukee.