DENVER -- Summoning Johnny Hockey! His scoring prowess is required ASAP.

After a 99-point regular season, Calgary All-Star forward Johnny Gaudreau has been held to a single assist and just 12 shots against Colorado. It is a big reason why the top-seeded Flames trail the Avalanche 3-1 in a first-round series that heads back to Calgary for Game 5 on Friday night (10 p.m. EDT)

Gaudreau's linemates, Sean Monahan and Elias Lindholm, have been held in check, too, with a goal apiece. Even more, captain and Norris Trophy candidate Mark Giordano has two assists in the series. This after finishing second in scoring among defencemen during the regular season.

No panic, though. Just action.

"Everyone has to look at their own games and be better," Gaudreau said. "We've got to get back to the way we were playing all year."

Either that, or summer starts early. The Flames are on the brink of being knocked out in the first round, just like Tampa Bay -- the top seed in the East.

Dating to the expansion in 1967-68, there have been various playoff formats in the NHL from division-based, conference-based and for two seasons, '79-80 and '80-81, the top 16 teams being seeded by regular-season points. At no point over that time have the top two teams in each division or conference -- or the teams with the two best records -- been eliminated in the first round, according to the league.

"It will be tough. Obviously we'd rather be 2-2 than 3-1," Lindholm said. "Go back to Calgary, we have a good crowd there for us, try to come back and play even better than (Wednesday) and hopefully get a win. Then it's game on again."

The Flames don't have a monopoly on vanishing stars in this post-season. Tampa Bay's Steven Stamkos and Nikita Kucherov had one goal and three assists between them in being swept by the Blue Jackets; while Sidney Crosby only had an assist as Pittsburgh lost four straight to the New York Islanders.

Nathan MacKinnon and Mikko Rantanen have been as advertised for Colorado. They have a combined six goals and five assists.

"Our depth," MacKinnon said, "is very underrated."

In particular, J.T. Compher (two goals) and Matt Nieto (two short-handed tallies).

"They don't get enough credit for what they've done all season, how much they've contributed," MacKinnon said of Colorado's supporting cast. "It's very encouraging that we can flip the switch. You don't have to play a perfect game to win."

Game 5 can't get here soon enough for Flames centre Mikael Backlund , who had a forgettable final flurry in a 3-2 overtime loss to the Avalanche on Wednesday. He took a late tripping penalty that led to Rantanen's tying goal in regulation. In overtime, Backlund had a perfect view on Rantanen's winning shot soaring right past him.

No time to hang their heads, though.

"We have nothing to lose now," Backlund said. "I don't think a lot of people think we can do it but we can. We've faced a lot of adversity and if there's any group I believe in and know they can do it, it's this group right here."

It starts with Gaudreau, who's been bottled up in the series with Colorado clogging the middle of the ice. Gaudreau and his teammates just can't seem to break free.

"We'll regroup," Giordano said.

Keeping them in games is goaltender Mike Smith , who's stopped 99 of 108 shots over the last two contests.

"I'm just one little cog," Smith said. "It's nice to have personal success but when you don't get the results it doesn't matter. You need to do more."

TORONTO at BOSTON (7 p.m. EDT)

The Bruins threw a wrinkle at the Maple Leafs by shuffling their lines. It did the trick during a 6-4 win Wednesday to tie the series at 2-2. David Pastrnak had two goals, while Brad Marchand added a goal and an assist.

Just the sort of boost the team was hoping for with Game 5 on Friday in Boston.

"We got some bounces" Wednesday, Marchand said. "Hopefully we get them next game."

The changes by the Bruins didn't bother the Maple Leafs as much as miscues.

"I thought our matchups were fine. That, to me, wasn't it," Toronto coach Mike Babcock said. "We just made some mistakes. Gave up some opportunities that we didn't need to give up."

Maple Leafs goaltender Frederik Andersen has already set aside the loss in which he surrendered five goals on 30 shots.

"Short memory," Andersen said.