DURHAM, N.H. -- The smiles beaming across the Boston College postgame podium while describing senior Kaliya Johnson’s game-tying goal on Friday night told the whole story.

For a team chasing a perfect season, a program fighting for its first national title and playing from behind for the majority of its Frozen Four semifinal against Clarkson, BC coach Katie Crowley, senior Haley Skarupa and sophomore Katie Burt knew how fortunate they were to have their season saved.

Johnson notched only her fourth goal of the season with just 3:53 left to play to force overtime, which the Eagles won 58 seconds in to steal a 3-2 win at Whittemore Center to advance to Sunday’s national championship game against the winner of Wisconsin and Minnesota.

And it wasn’t the type of goal you’d expect from the high-flying Eagles (40-0-0).

It seemed like another disappointing possession for BC. Clarkson’s stifling defense had executed its game plan to near perfection in blocking shots and frustrating the Eagles with their physicality. BC sophomore Megan Keller corralled the puck behind the Clarkson (30-6-5) net, seemingly out of options as she pivoted, swung her body around and threw the puck in front.

At first glance, nobody was home. Clarkson’s Olivia Howe had positon on Johnson in front and tried to intercept the pass, but it glazed off her skate and landed on the extended stick of Johnson. The senior merely threw a shot on goal that somehow evaded Clarkson goalkeeper Shea Tiley to sneak past her right pad for the equalizer.

It was one of those goals that had to be seen on replay to make sure you saw it correctly.

“We’ve talked a lot this year about putting pucks on net quickly without stickhandling, without waiting too long and letting the goalie set up,” Crowley said. “Kaliya just put that one in the right spot. It wasn’t the hardest shot, it wasn’t the most dynamic shot you’ve ever seen, but she let it go right away and put it in that corner and I think everybody jumped almost as high as the boards.

“Obviously after that, you know you have a chance now.”

It was a situation unlike any BC had faced this year. Never had the Eagles trailed after the first period or the second. They’d only been tied heading into the third period on two occasions, although they did have an OT win against Boston University under their belt.

Their desperation was evident as the game moved to the latter half of the third period. BC’s sloppy play to start -- helping to put them in a 2-0 hole before Skarupa’s first goal of the night cut the score in half in the second -- was traded for mad rushes in Clarkson’s end.

“We just realized that we need to revert to what we’ve been doing all season,” Skarupa said. “We’re a team that really trusts each other and we know we can rely on each other, so we just took a deep breath and were like, ‘Yeah, we’re in a desperate situation, but we’ve been doing this all season. We can trust each other all over the ice.’”

But the Golden Knights’ recipe of physicality and blocking shots (24 for the game) seemed to have the Eagles destined for a disappointing end result in a quick exit from the Frozen Four. Not even three consecutive penalties by Clarkson, resulting in an extended 5-on-3 advantage for the Eagles, could yield that tying goal.

But Johnson’s tally turned the tide. The BC cheering section, relegated to merely observers of the inevitable, were struck with a bolt of energy. Clarkson, in control the entire game, had its collective gut punched.

The extra bolt in their skates might have been the difference in the end. BC senior Alex Carpenter fought off Clarkson’s Shann MacAulay along the boards in the Golden Knights’ end in the first minute of OT to maintain the Eagles’ possession. It ended up being the difference, as Carpenter laced a beautiful, cross-ice pass to Skarupa waiting at the doorstep of the cage to finish the game-winner.

When her shot crept past the extended Tiley, Skarupa chose the optimum word to describe the moment: relief.

And now the perfect season lives on. The Eagles’ quest for their first national title has merely one obstacle left, against a team with plenty of championship experience.

But it might be nothing compared to the obstacles of Friday night.