Air Force won the Atlantic Hockey Association tournament five times in its first six seasons in the league. That impressive run is over.

The two-time defending tourney champions lost a second straight game at Cadet Ice Arena as seventh-seeded Canisius toppled the No. 2 Falcons 4-3 on Duncan McKellar’s overtime goal before 1,907 disappointed fans Saturday.

“We’re no doubt the better team,” Air Force junior goalie Jason Torf said. “Looking in the eyes of my seniors is the most disappointing part. Now we won’t see this team develop fully and see how far we could go in the NCAAs.“

Air Force (17-13-7) has struggled in close encounters, with a 2-9 record in games decided by one goal. Canisius (17-18-5) was 0-2-1 in three regular-season games against the Falcons.

The Falcons were seemingly in control with a 3-1 lead late in the second period, and a 3-2 edge with 2 minutes left in regulation. But Canisius center Matthew Grazen scored with 1:58 left to tie the game and steal momentum.

“You can’t say we sat on a lead,” said frustrated Air Force coach Frank Serratore, whose team outshot the visitors 12-3 in the third period. “Their goaltender was great.”

Canisius goalie Tony Capobianco ranked third in the league in goals against and survived a 53-25 Air Force edge in shots on goal.

“He is a special goaltender but he’s not the only piece we have,” Canisius coach Dave Smith said. “It’s a big upset because it’s (seeds) 7 and 2, but we felt differently in our locker room than what the standings indicated.

“Air Force knows how to win but this was a big character win for us.”

Air Force erased a 1-0 deficit with goals by Ben Carey with 2 minutes left in the first period, and Adam McKenzie’s less than 3 minutes into the second. McKenzie scored again midway through the second period before Kyle Gibbons got Canisius within a goal at 16:33 of the second.

McKellar’s game-winning shot from the right circle deflected off a Falcons defenseman and soared over Torf.

“Two guys were in front of me and I went down to block the puck,” Torf said. “I heard people saying up, up and I slid back in my crease.”

Replays showed that the puck came down behind Torf, bounced off his pad and his momentum carried it into the net.

“Plain and simple, we’re too good of a team to be going out this way,” Falcons sophomore Chad Demers said. “We outplayed them both nights. We know we’re the better team.”

Serratore said losing Friday’s game was the problem and that the Falcons had still been confident of a long postseason run.

“We were quietly one of the hottest teams in the country,” he said. “Since December, we were 14-4-4 and primed for a run in the NCAA Tournament.”

Air Force is 10-1 in Rochester, N.Y., site of the AHA’s final four. They’ll have to wait until next year to improve on that mark.