In a seesaw Catholic League baseball game Sunday, Archbishop Shaw collapsed, hammered its way back upright, squandered its lead and toppled over again before somehow surviving 9-8 against Brother Martin in nine innings at Wesley Barrow Stadium.

Kyle Flettrich smashed a winning two-run double to deep right to lift the Eagles (16-11, 3-4), who trailed 8-7 entering the bottom of the ninth.

“It wasn’t so much me. The best hitter in the city (Jace Nini) decides to give himself up to give me the chance,” Flettrich said. “I expected a fastball away. Been throwing it all day. Finally jumped on him.”

It was the Eagles’ second consecutive win in league play; the first was an 8-4 upset of Holy Cross on Saturday.

Shaw had nine runs on 16 hits while stranding 15 runners against Brother Martin (15-10, 3-4), which had seven hits and left 11 on base.

“It’s never easy in this league,” Crusaders coach Mark Wisniewski said. “Every one is tough. We have to compete and do our job. We gave them some extra opportunities that we shouldn’t have done, and they took advantage. When you’re playing quality opponents, you have to make the plays.”

Identical situations yielded disparate results for the Crusaders and Eagles early. In the bottom of the first, Brother Martin pitcher Keagan Gillies put himself in a one-out, bases-loaded jam behind consecutive walks. The damage? Minimal, as Shaw squeezed out two runs on one hit to take a 2-1 lead.

Two innings later, an error at shortstop put pitcher Keith Meier and the Eagles in their own precarious spot, which cost them — four runs, to be exact.

But Shaw answered. Lance Landry, Nini, Nick Carbo and Caiden Reid had RBI hits in the third, fourth and fifth innings to put the Eagles ahead 7-5 before Brother Martin staved off defeat in the seventh.

Meier fanned the first batter, then Shaw coach Kyle Bullinger summoned Flettrich from the pen.

“His pitch count had climbed,” Bullinger said. “We gave him the one lefty batter and then wanted to try our luck with (Flettrich) against the righties.”

The ensuing sequence unfolded as follows: strikeout, hit by pitch, walk, walk, game-tying RBI walk, strikeout. Brother Martin retired the side on a strikeout, flyout and groundout in the bottom of the seventh, sending the game to extra innings.

It appeared the Crusaders would complete the rally when Blair Frederick singled to shallow center to score Michael Kirsch and forge a 8-7 lead in the top of the ninth.

But Shaw scraped together enough to counteract the blow. The Eagles doubled and placed a bunt to pad the bases for Flettrich.

Game over.

“We botched a bunt coverage, which allowed them to get two on, and they put a swing on it,” Wisniewski said.