Bill Walton, the backup center for the...

Bill Walton, the backup center for the Boston Celtics who has not played a game this season because of an ankle problem, has had another setback.

Walton had a second bone scan of his right foot, which revealed abnormalities.

Walton injured his ankle during the first week of October while using an exercise bicycle.

The 6-foot-11, 235-pound Walton, a former UCLA star, was acquired by Boston from the Clippers in a trade Sept. 6, 1985. Last season, he averaged 19 minutes and 7.6 points a game.