MRI shows Wallace's left knee not severely damaged
Wallace was helped off the floor with just over 5 minutes left in Saturday's 100-97 victory after Haslem's head hit his knee. Wallace, who had 15 rebounds, is listed as day to day.
The Bulls start a seven-game trip Wednesday, when they visit the Los Angeles Clippers.
"We're very happy that Ben's injury doesn't appear to be serious," trainer Fred Tedeschi said in a statement. "We hope to know more, in regard to his return to the court, in the next couple of days."
Wallace is averaging 6.5 points and 10.1 rebounds in his first season with the Bulls.
Copyright 2007 by The Associated Press
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