During the 1969 Stanley Cup playoff opener between the Boston Bruins and Toronto Maple Leafs, Bruins player Pat Quinn delivered a huge hit on Maple Leafs defenceman Bobby Orr which knocked Orr unconscious. Kennedy responded by taking part in four fights and punching a linesman after the last fight. He was fined $1,000 for punching the linesman. He was suspended for a long time and his time with the Maple Leafs ended. It was also the last game he played before he was forced to retire because he never recovered from knee surgery.