The Washington Capitals hoped that having to win Game 1 of the Stanley Cup playoffs in overtime, after blowing a 2-0 lead in the final 10 minutes, would be enough of a lesson. But in Wednesday night’s Game 2 against the Montreal Canadiens, the third period looked very similar to the one from two nights earlier.

The second time around, Montreal wasn’t able to score, thanks in large part to a superhero-esque performance from goaltender Logan Thompson, and the Capitals hung on to win. As a result, they have a 2-0 lead in the series as it shifts to Montreal for Game 3 on Friday, but they know how thin the margins have been.

“We’d like to be on our front foot a little bit more,” forward Connor McMichael said Wednesday night. “ … It might be a little bit mental. It might be just trying to protect the lead too much. But I think the first two periods showed when we’re playing in their zone, they struggle breaking it out and we’ve just got to continue to be physical.”

Across both games in the first two periods, the Capitals have outshot the Canadiens 50-33 and generated 28 high-danger scoring chances, per Natural Stat Trick, to Montreal’s nine. But in the third periods, the Canadiens lead 28-12 in shots and 8-1 in high-danger chances.

Washington has struggled in both third periods to break the puck out cleanly and handle the Canadiens’ surging momentum. The Capitals expect a push, with Montreal trailing in a playoff game and fighting for its life. But they’ve so far seemed unable to handle it, even when they see it coming.

“When teams are down, they play a different style. They obviously played more aggressive, and we just can’t sit back,” defenseman Jakob Chychrun said Thursday. “We just need to continue to play the way we were the first two periods. When we’re predictable out of our own end, breaking out pucks well and getting on our forecheck, we’re getting a lot of sustained [offensive] zone time and a lot of puck possession and good chances. I think [we need to] continue to stick to that when we have leads and just not change it.”

When Washington Coach Spencer Carbery discussed the third period in the immediate aftermath of the game Wednesday, his impression was straightforward.

“That’s not us,” he said. “And very uncharacteristic, just some of those mistakes that we don’t normally make.”

After taking a look at the film and watching the period over again, Carbery saw the “group effort” of those mistakes and turnovers, which were rarely the fault of just one player but often the result of poor communication and a lack of support around the puck.

“As the temperature rose in the game, as we struggled with that, it started to snowball,” Carbery said. “More mistakes, more poor reads, and I look at it, too — it’s not just about one guy. A lot of times, you’ll see, like, we had multiple turnovers through the neutral zone, on the defensive walls. You look at it like, ‘That guy’s got to get that puck out. He’s got to make that play.’ But I also look at the other four guys. What do they do to help him under pressure, when the [Montreal defense] is slamming down the walls? It’s not just isolated things.”

The temperature at Bell Centre on Friday night will be as high as the Capitals have experienced so far in this series. In the NHL’s largest building, more than 21,000 fans will create an atmosphere that, as Carbery put it, will make it so “[you] can’t hear yourself think.”

“Your natural tendency is to protect the lead, but that’s when bad things can happen,” Chychrun said. “We’ve had to rely on [Thompson] to bail us out a couple times. A lot of it can be mental. These are obviously high-pressure games, loud atmosphere. Tough to communicate. That’s when you got to rely on your details and your structure.”

Though the Capitals have a two-game lead, their ability to handle the pressure that they know is coming on Friday will be a bellwether for how the series continues. They escaped with two home wins and have been the better team for at least 80 of the 120-plus minutes. But those other 40 have gotten dicey, and the clichéd 60-minute effort has never felt less clichéd than it does to Washington right now.

“One thing is executing through the pressure. The second thing is not letting it snowball,” Carbery said. “I’ve talked a lot about this through the series and through the playoffs is momentum. When you get it, how do you hold on to it? And when you lose it, how do you stop them as quickly as you can? That’s just what we didn’t do [in the first two games].”

Note: Winger Aliaksei Protas, who has been out of the lineup since he was cut on the top of his left foot by a skate blade on April 4, is traveling with the team to Montreal. Protas has skated on his own this week, steadily increasing his workload and incorporating skills sessions as the week went on. Carbery said Monday that he’s optimistic Protas will play at some point in this series.