Monahan, the sixth player taken in the NHL Draft last June, scored his second goal of the game 1:50 into overtime to lift the Flames to a 2-1 win against the Edmonton Oilers at Rexall Place on Saturday night.
Calgary's prized 19-year-old took a pass from Paul Byron in front of the net and slipped a shot through Oilers goaltender Ilya Bryzgalov to snap the Flames' two-game losing skid with his team-high 18th goal.
"It was kind of a must-win game for us," Monahan said. "It was pretty intense. After [Kevin Westgarth] goes to war like he did, you have to find a way to win. Fortunately enough we did."
Westgarth was injured in a fight with Edmonton's Luke Gazdic immediately after Monahan's goal at 10:15 of the first period.
David Perron scored the lone goal for the Oilers, whose losing streak reached three games.
"In overtime [Byron] was just buzzing all over the puck and made a great pass to me, which fortunately enough, I was able to bury," Monahan said. "I was surprised that I had so much room, so it is something you have to bury at a time like that. That was pretty awesome. That is my first overtime goal in the NHL. We just want to win as many games as we can at this point."
"I thought we did a good job, we had a lot of chances," Flames captain Mark Giordano said. "Our defense did a good job of beating them up ice and our forwards were making great plays. We don't like giving up that point, but I thought we played a great game, stuck with it and got rewarded.
"One thing we have learned about [Monahan] is that he doesn't miss too many of those chances around the net. He has a knack for putting those ones in. Good on him. I am happy for him."
The Oilers and Flames came into the game after being shut out at home Thursday night in their first game following the break for the 2014 Sochi Olympics. Edmonton lost 3-0 to the Minnesota Wild; Calgary was beaten 2-0 by the Los Angeles Kings.
"In our own zone, for the most part, I thought we were all right," Oilers coach Dallas Eakins said. "The last goal was just a great lesson for our defenseman [Martin Marincin] there. You have to win the battle. It's a simple battle and that's what happens when you lose a battle like that, especially 4-on-4.
"Defensively we were OK, but we still have to find more offense. We'll go right back to it in practice and continue to get those touches. But our top guys have got to find a way to generate more."
Each team has been shut out eight times this season. The Oilers were less than 11 minutes away from a ninth shutout loss before Perron tied the game at 9:43 of the third by firing a shot over Berra's shoulder. The goal ended Edmonton's shutout streak at 160:47 -- the Oilers had not scored since Taylor Hall's goal at 11:30 of the first period of a 2-1 overtime loss to the New Jersey Devils on Feb. 7, prior to the Olympic break.
One reason for Edmonton's offensive struggles is a power play that's 0-for-19 in its past six games. The Oilers were 0-for-2 Saturday.
"On the power play we're having troubles entering the zone and we're having troubles finishing," right wing Jordan Eberle said. "On the one power play, we must have had four or five chances and we couldn't capitalize. When that starts to happen, that starts to wear on you and you start doubting yourself.
"For me personally the biggest thing with our lack of offense, and we seem to go through it every season, is that our power play is dead."
Eberle has been held scoreless in his past six games. Hall, the team's leading scorer, has a goal and an assist in that span.
"There were a few pucks laying in the crease and a few chances, but at the end of the day, you have to get goals," Hall said. "It's hard to play when you're trailing the whole game. We got a nice goal from the [Sam] Gagner line, but, really, not enough offence from the offensive guys."
The loss dropped the Oilers five points behind the Flames at the bottom of the Western Conference standings. They continue a five-game homestand Tuesday against the Ottawa Senators. The Flames visit the Minnesota Wild on Monday.
"I don't really know if there's any prize for points now," Hall said. "We're not in the playoffs and it's not like we're trying to race up the standings to get into a playoff spot. We know where are. We need to win games. Overtime losses aren't enough."