"St. Louis Blues ownership and myself realize how integral Andy is to the future of our organization," said Davidson. "He's a first line center who will play a major role in the development of our team."
McDonald, 31, is in his eighth NHL season and has registered 18 points (six goals, 12 assists) in 16 games this season. He's been sidelined for the past 35 games due to a fractured left leg. He has recorded 16 points (four goals, 12 assists) in 33 games with the Ducks this season.