P.K. Subban scored 23 seconds into overtime to give the Canadiens an improbable 5-4 victory over the Senators Thursday night at the Canadian Tire Centre. Montreal allowed 44 shots and only an inspired performance by Carey Price kept the Canadiens in the game. In a game filled with bizarre twists, Tomas Plekanec was credited with the tying goal at 11:02 of the third period. Craig Anderson stopped Plekanec on a breakaway but the rebound caromed off the skate of Ottawa defenceman Jared Cowen. Saving their best for last: The Senators scored twice in the final three minutes of both the first and second periods. Bobby Ryan scored off a rush at 17:16 of the second period to tie the game at 3-3 and Kyle Turris gave the Senators their first lead when he scored at 18:40. Erik Karlsson picked up an assist on the Turris goal to complete a three-point night. Making the most of their chances: The Senators enjoyed a wide edge in terms of puck possession in the first period, but the Canadiens scored on three of their first five shots to take a 3-0 lead. Plekanec opened the scoring when he was sent into the clear by Travis Moen and scored on a short-handed breakaway at 2:04. The struggling Montreal power play ended a five-game drought when David Desharnais found Max Pacioretty alone in the slot and Pacioretty beat Craig Anderson for his 21st goal of the season at 14:05. Desharnais, who was a game-time decision after missing Tuesday’s game against New Jersey because of the flu, took a pass from Brendan Gallagher and walked in alone on Anderson at 15:36.