Ryan Nugent-Hopkins scored 2:55 into OT after taking a pass from Connor McDavid, lifting the Oilers over the St. Louis Blues 3-2 on Monday night.
The winner came after Patrick Maroon, a St. Louis native, got his first goal in nine career games against the Blues by tipping a shot by Brandon Davidson 5:47 into the third period.
Cameras caught Maroon's son Anthony celebrating the score in the stands, and Maroon cried when he was shown the video during a postgame television interview.
''I don't get to see him as much,'' he said, choking back tears. ''It's pretty special.
McDavid became the first NHL player with 40 points by assisting on the OT goal.
The OT goal frustrated St. Louis goalie Carter Hutton, who stopped 32 shots on his 31st birthday. It was his first start since Dec. 3, when the Blues lost to the Jets in overtime.
St. Louis scored first when Kyle Brodziak connected on a wrist shot 4:20 into the game. Nugent-Hopkins tried to poke the puck over the blue line, but Kevin Shattenkirk got it and passed to a wide open Brodziak, who beat Cam Talbot on his glove side.
Edmonton tied at about seven minutes later. Leon Draisaitl won a faceoff and Tyler Pitlick buried the shot, beating Hutton on his right side. Draisaitl also assisted on Maroon's goal.
The Blues took the lead back 33 seconds later when Vladimir Tarasenko hit a wrist shot from the right circle.
Tarasenko leads all NHL players with 15 points (six goals and nine assists) in December. Tarasenko has points in 17 of his last 21 games with 12 goals and 17 assists.
The Blues are at Dallas tonight.