The Red Sox activated David Wells from the disabled list on Friday night but the left-hander got hurt again when he was struck on his injured right knee by a line drive. An examination showed a deep bruise but "no immediate evidence of a serious injury," according to team medical director Dr. Thomas Gill. Wells will be examined further on Saturday. The 43-year-old Wells has been sidelined most of the season because of a sprained right knee. He had been on the disabled list since April 14, two days after he struggled in his only other start of the season. He left Friday night's game in the fifth inning when Tampa Bay's Travis Lee hit him with a batted ball.