Did the frustration boil over?
Anger get the best of him?
Or was it simply a pledge to his teammates - a 'follow along, boys,' lead-by-example-type play that helped the set the tone the rest of the way.
Maybe it was all three.
Whatever the reason, when Hampus Lindholm was caught flat-footed, flubbing an outlet pass at his own blueline on Sunday in Anaheim, he could hear the footsteps a good 10 feet away.
Sean Monahan had locked on, pumping another two strides before barrelling in and delivering a massive open-ice crunch that dropped the 6-foot-3, 210-lb. defender in a heap inside his own zone.
This wasn't a one-time occurrence, either.
The aggression, the bite, with which Monahan is playing with right now isn't going unnoticed.
"I thought Mony was outstanding in Anaheim," said Head Coach Bill Peters, applauding the centre.
"For Mony, I've definitely seen it all season. Much more physically engaged, more involved, better defensively. We don't want it to take away from their offence, obviously. You'll see those guys start to produce some points here moving forward, at a certain level of consistency offensively.
"They know they can get to another level and now would be a good time."
Monahan didn't record a point in Sunday's 2-1 victory, but he may as well have, as the catalyst to a key goal by Michael Stone late in the second period.
No. 23 was involved in a fiery net-front battle, pushing and shoving with Anaheim rearguard Michael Del Zotto, as both looked to establish body position at the crest of the blue paint.
Monahan got the better of his opponent, badgering him with a stiff blow between the shoulders and taking away the stick at the most opportune time.
Stone's one-time blast flew clean past netminder John Gibson, who was unable to see thanks to the timely screen set by Monahan.
Video: "That's where you have to be to score goals"
Points aren't everything, and right now Monahan is setting the very best example of how to play away from the puck.
"That was my goal over the summer, to be more reliable, better in my own zone," he said. "I think right now it's paying off.
"We're getting our chances; they're going to come. But right now, it's the little details of the game where we want to be better. It's getting there.
"Personally, I feel better. When you feel healthy and feel strong, your game can change."
Monahan has only two points in his last five games, but the coach isn't concerned in the slightest.
He wants Monahan - along with Johnny Gaudreau and Elias Lindholm - to continue their strong, transitional play in the defensive zone. It's there where the Flames have had trouble, at times, this year, feeding into the opponent's counter-attack and forcing either David Rittich or Cam Talbot to play hero.
Really, it's a plan that all 18 skaters have to buy into, but considering the top line plays the bulk of the minutes, they set the roadmap, the "template," for the others.
From there, ratchet up the intensity and go to work where it's the toughest, like Monahan did on the Stone goal.
Video: "They know they can get to another level"
"You can go get three points and be minus-6 and get the (crap) kicked out of you and lose the game," reminded Peters. "Anyone want to do that? You want to cheat for offence and lose hockey games - does anyone want to do that? Or do you want to win hockey games? What do you want to do? Do you want to lose 9-8?
"I don't want to give up freebies, right? And we've given up some freebies this year.
"Don't give up the freebies, dial in, get on the inside offensively. We all know where you've got to go to score, right? If you're going to rob a bank, you've got to go to the bank. If you want to score, you've got to go to the net.
"Go to the net. Get on the inside, get on the guts of the game."
This was this was one especially passionate monologue, with Peters repeatedly smacking his hands and reminding the dozen or so reporters gathered outside the Flames locker-room that, yes, the old chorus rings true:
Do that and do it well, and the offence will come.
"Game 1 of the World Series tonight," the coach said with a chuckle. "Who do you have?
"Houston. Pretty good pitching. Silences the bats. Defence over offence. The Yankees are a good offensive team. Houston? Pitching. … If you play good defence, you're going to get lots of offensive opportunities.
"If you play (bad) defence, good luck getting out of your own end.
"The teams that are efficient in D-zone transition, they're never in their zone. The puck goes in, the puck leaves, you come through the neutral zone with speed, you go into the offensive zone, you have fun for 30 seconds, the goalie robs you, he makes the save, you put a new line out and do it again.
"Getting hemmed in… and when you get the puck, you flip it out and hustle to the bench, and now the other guys are under siege? Painful. Painful to watch. It happens to everybody around the league at certain times.
"Just make sure it's not us."