Colorado's Xavier Johnson tears Achilles

BOULDER, Colo. -- Colorado senior guard Xavier Johnson underwent surgery to fix his torn left Achilles tendon.

There is no timetable for his return after he suffered the injury in an offseason workout earlier this month, the school announced Thursday.

Coach Tad Boyle said in a statement the Buffaloes are "looking forward to helping Xavier through this process and getting him back healthy, and help this program win more games."

The 6-foot-7, 230-pound Johnson averaged 10.3 points and 5.6 rebounds per game last season.

Colorado begins its season Nov. 13 against Iowa State in Sioux Falls, South Dakota.