LYNN — A pair of Catholic Central League rivals locked horns in a Division 3 softball quarterfinal on Saturday that won’t soon be forgotten.

No. 9 Bishop Fenwick (15-9) received a two-run single from Katie O’Brien in the top of the ninth inning to break a scoreless tie in pulling off a 2-0 shocker over No. 1 St. Mary’s (20-2) at Grace Rogato Field.

The Crusaders, winners of 10 straight, move on to face Norton in the state semifinals.

“That was just nuts,” Fenwick coach Brian Seabury said. “Katie did a great job of hitting the ball where it was pitched and got us the hit that we needed.”

It felt like neither team was going to score as Spartans hurler Anna Fringuelli and her counterpart, Gigi Aupont, traded zeroes for over two hours. But in the ninth, it was Fringuelli and the Spartans who blinked first.

Walks to Mia Mercurio and Aupont began the frame. After a sacrifice from Sophia Longo, O’Brien swung at the first pitch and dumped a single into short right to give her team the lead.

The rest of the job was left to Aupont, who danced out of jams in the fifth and sixth and seventh innings to keep the game scoreless.

After Fringuelli reached on a leadoff error, Aupont (CG, 4 hits, 8 strikeouts) got back-to-back groundouts before she made a spectacular diving catch on Michaela Walker’s pop-up to end the game and spark a wild celebration.

“I kind of equate what Gigi does to being a goaltender in hockey that makes 40 saves a game,” Seabury said. “That’s just the way she pitches and we expect that from her every time she goes to the mound.”