Leon Draisaitl had four assists, and Mike Smith made 29 saves for the Oilers (30-17-2), who split the two-game set following a 3-1 loss here Thursday and moved five points ahead of the Winnipeg Jets for second place in the Scotia North Division.
"I thought we came out with a lot of jump tonight," Smith said. "The last game wasn't ideal, a back-to-back for us, and you could tell our energy level was as low as I've seen it for a long time. And tonight was the opposite. We were jumping. The first period was real solid, and I don't know if we thought they were just going to go away, but they kept coming at us and we sat back a little bit and didn't do anything to push the game along."
Johnny Gaudreau scored, and Jacob Markstrom made 25 saves for the Flames (22-25-3), who have lost two of their past three games and fell eight points behind the Montreal Canadiens for the fourth and final playoff spot in the North with six games to play.
"We came back in the second period and we just couldn't get the tying goal," Calgary coach Darryl Sutter said. "Connor's got 18 or 19 goals in this rink this year, so you best start the game right up the middle or that gets you in trouble. So you're chasing the lead and don't score enough goals. When you get down two, it's tough in this building."
McDavid scored on the power play at 4:46 of the first period to give Edmonton a 1-0 lead. He took a pass from Draisaitl in the neutral zone before skating around defenseman Chris Tanev and beating Markstrom glove side.
Ethan Bear made it 2-0 at 7:19 on a one-timer from the bottom of the left face-off circle off a pass from McDavid.
"We probably gave up 10 scoring chances in the first 10 minutes. It probably should have been 5- or 6-0 if [Markstrom] didn't play so well," Tanev said. "He gave us a chance to win, and obviously we didn't get the job done."
Gaudreau cut it to 2-1 at 10:48 of the second period when he scored off the rebound of a shot by Matthew Tkachuk.
"I didn't love our second period, even though we had that power play and I had a chance to put the game away and a couple of guys had chances," McDavid said. "To put them down 3-0 would have been huge, but we kind of gave them life and I thought they took over the second period. The third period, I thought we did a good job holding the lead."
Josh Archibald (18:54) and Darnell Nurse (19:34) each scored into an empty net in the third period for the 4-1 final.
"I like the way we started the game. We started really well and then we took two penalties, which took the momentum away from us," Oilers coach Dave Tippett said. "Give Calgary credit, they pushed hard the whole game, but we hung in there and we were able to get the win.
NOTES:McDavid played his 400th NHL game. He has 556 points (191 goals, 365 assists) ... Gaudreau has eight points (three goals, five assists) during a seven-game point streak.
