Boston Fleet goalie Aerin Frankel is the best in the PWHL, in the eyes of her head coach, Courtney Kessel. But Kessel has also said she wants Frankel not to have to be called upon for a 57-save performance, like her record-setting playoff win over Montreal last year.

And yet, early on in the Minnesota Frost's 2-1 road win against the Fleet on Wednesday night, the 25-year-old goalie weathered a barrage of Frost shots.

But that could only last so long. After having their home opener spoiled by the New York Sirens on Sunday, the Frost (1-0-1) did the same to Boston, thanks to a game-winner from rookie Dominique Petrie.

It was a rematch of last season's Walter Cup best-of-five finals, which Minnesota won 3-2. In Game 5, Frankel made 38 saves, but the Frost, then dubbed "PWHL Minnesota," clinched the league's inaugural title with a 3-0 win on the road.

"It's hard to win this thing, and now we have players who are learning every game, it's going to be a one-goal game," Frost coach Ken Klee told reporters in Boston. "Every game is going to be tight and every game is going to be contested."

Petrie made sure Minnesota extended its win streak to three in Boston. She deflected a deep shot from Mellissa Channell-Watkins into the net with 10 minutes left in the third period.

A fifth-round draft pick who played at Harvard and Clarkson, Petrie also scored the goal that forced Sunday's 4-3 loss into overtime.

"[My teammates] have given me the confidence to play with pace, play my physicality," Petrie said. "I'm fortunate to have a lot of veterans in that group to learn from, and that can carry me along the way."

The win was, at its core, a cleaner version of the season-opening loss. The Frost again outshot their opponent, directing a goalie highlight reel and playing a smothering forecheck. Klee said he liked their odds in a performance like Sunday's, and Wednesday was a case in point.

Boston (0-2-0) netted the least amount of goals in the six-team league last season and stayed close early in its home opener thanks to Frankel, a former Patty Kazmaier award winner at Northeastern who posted 26 saves on Wednesday.

Frost center Michela Cava opened the scoring in the second period. Taylor Heise, cornered against the boards behind the net, flicked a no-look pass to Cava at the crease, and she popped the puck over Frankel.

"I think following last year, and then this year, I feel like [linemates Heise, Kendall Coyne Schofield, and I] have really good chemistry," Cava said. "It's all three of us doing one job… It's been a lot of fun to play with them."

Boston evened the score with 16 minutes to play. Four-time U.S. Olympian Hilary Knight tipped a rip from Emily Brown into the net.

Frost goalie Maddie Rooney came up big early and late, giving up few rebounds on her 20 shots faced.

Resuming last year's back-and-forth goalie tandem, Rooney stepped in for goalie Nicole Hensley, who started Sunday's home opener.

Minnesota went 0-for-3 on power plays and now is 0-for-5 on the season and the last team without a power-play goal.

The Frost's road trip continues to Toronto (1-1-0), where they will drop the puck at 1 p.m. Sunday against last year's No. 1 playoff seed, which Minnesota reverse-swept in the semifinals.

After a one-week international break for the women's Euro Hockey Tour, the Frost will resume league play hosting the Ottawa Charge on Dec. 19.