The San Francisco 49ers have appealed a...

The San Francisco 49ers have appealed a court ruling that claims they fraudulently concealed the severity of a crippling knee injury to former lineman Charles Krueger, saying the decision poses a “limitless expansion” of liability that would hurt all competitive sports.

In papers filed this week with the California Supreme Court, the 49ers asked for reversal of a Feb. 20 decision by a state appellate court holding them responsible for injuries that have left Krueger unable to stand for prolonged periods.

In its ruling, the First District Court of Appeal said that the NFL team had defrauded Krueger by failing to tell him the risk when he played in severe pain for the last 10 years of a 15-year career that ended in 1973.