ST. LOUIS -- Standing at the other end of the ice, Brian Elliott knew exactly what Jake Allen was thinking.

What exactly is a goalie supposed to do?

Allen and the St. Louis Blues experienced a frustrating loss on Saturday night when all three Calgary goals deflected off one of his teammates and into the net, including the game-winner with 2.5 seconds left in overtime, which gave the Flames a 3-2 victory.

Sean Monahan got credit for the goal when his would-be pass instead hit off Blues center Kyle Brodziak and past Allen just when it appeared the game was headed to a shootout.

"It was like a foot away from me and banked in," Allen said. "I couldn't do anything."

Monahan almost sounded sorry for Allen.

"You never know when you throw pucks at the net, anything can happen," Monahan said. "That's a good bounce, a lucky bounce, and we'll take it."

It was actually the third of three good bounces for the Flames, who scored their first two goals when the puck deflected off Blues defenseman Jay Bouwmeester.

Former Blues player Troy Brouwer scored on a power play late in the first period -- breaking Calgary's 0-for-12 streak with a man advantage -- when his shot deflected off Bouwmeester and went over Allen's glove.

In the third period, after the Blues had taken a 2-1 lead, Flames defenseman Matt Bartkowski scored his first goal of the season when his shot went off Bouwmeester's skate and into the net.

"It's tough when all three goals go in off your own guys," said Blues defenseman Alex Pietrangelo. "I feel bad for Jake, to play the way he did. Tough bounces, but we got a point out of it."

The loss snapped a four-game winning streak for the Blues while the Flames, battling to hold onto the top wild-card spot in the Western Conference, halted a two-game losing streak.

How the Flames won didn't really matter to coach Glen Gulutzen.

"I didn't even see it," Gulutzen said of the winning goal. "I jumped when everybody else jumped and it was kind of like I didn't get the joke right. Everybody got the joke; I didn't. I just jumped because I saw everybody else jump."

Said Elliott, "I was just getting ready for the shootout and I was happy to skate down to the other end full speed into the pile."

The Blues fell one point behind Nashville for third place in the Central Division, dropping them into the second wild-card spot in the West. They trail the Flames by two points in the race for the wild-card spots.

Allen lost for only the second time in his last nine starts, having given up a combined nine goals in the previous eight games.

"Overtime can give you a little bit of a sour taste," said Blues coach Mike Yeo. "I look at the game the same way we've been looking at the wins. There were parts of our game that were good and some parts we need to be a little better.

"We're not going to sit here and complain about breaks and bounces. We didn't get the win."

After falling behind 1-0, the Blues tied the game on a goal by Ivan Barbashev at 8:08 of the second period. His was the only clean goal of the night, as his initial shot was blocked in front of the net but he stayed with the puck and shot it past Elliott.

The Blues pulled ahead at 7:16 of the third period when Jaden Schwartz knocked in a rebound of a shot by Brodziak. Both Schwartz and Elliott ended up in the goal, which was confirmed after a video review.

The Flames had a chance to win the game at the end of regulation when they got a power play with 2:04 to play when Pietrangelo was called for delay of game, but could not score, sending the game to overtime.

"We knew it was going to be a tough ride coming in here," Elliott said. "We knew it was going to take 60 minutes or more and that's what happened. All these teams are in the hunt and on top of their game right now. Getting this win was big for us. Every game is going to be big."

NOTES: This was the first time in their careers Brian Elliott and Jake Allen opposed each other in goal. They were teammates on the Blues from 2012-2016. ... LW Matthew Tkachuk returned to the Calgary lineup after serving a two-game suspension for elbowing Kings D Drew Doughty. ... The Flames signed D Josh Healey from Ohio State to a two-year entry-level contract on Saturday. Healey will join the Flames' AHL affiliate the Stockton Heat for an amateur tryout. ... The Blues will complete a three-game homestand on Monday night against Arizona while the Flames go back home to play Colorado on Monday night.