BUFFALO, N.Y. — You never know who will step up come NCAA tournament time.

Backup goalie Chris Reynolds was a steadying presence in a spot start, while attackman Justin Mayfield nearly matched his previous season total in goals in Robert Morris’ 12-6 road victory against Canisius in the NCAA men’s lacrosse tournament play-in game on Wednesday. With the win, the Colonials earned a trip to College Park to meet top-seeded Maryland on Sunday at noon.

The commanding performance in the program’s first postseason triumph added fuel to the argument that Robert Morris’ resume warranted better than the play-in game.

“We didn’t expect to be in a play-in game with where we were from an RPI standpoint and the makeup of our resume throughout the year,” Colonials coach Andrew McMinn said. “Once they put us in that position, at that point we just said, ‘Hey, we’ve got to go out there and do our best to show that we can compete no matter what they tell us to do.’”

Reynolds, who earned his first career collegiate win, learned Tuesday night he’d be starting in place of Alex Heger, the Northeast Conference Goalie of the Year. Heger suffered a lower-body injury two days before the Colonials’ postseason debut.

“It was a little rollercoaster,” Reynolds said. “Once game time came, the support from my teammates helped me settle down.”

Reynolds wasn’t tested often, as the Colonials’ top-tier defensive unit only allowed 12 shots on goal, but was sharp enough (six saves) to consistently keep the Golden Griffins at arm’s length.

“I just have to be prepared every week to be in that position,” Reynolds said. “I was ready to go.”

McMinn said Heger’s availability for the Maryland game is unknown.

Mayfield entered Wednesday’s matchup with four goals on the season but paced the Colonials with three tallies against the Griffs. He was one of eight Robert Morris players who beat Canisius goalie Liam Ganzhorn.

“When you’ve got Jimmy [Perkins] flying around back there, doing two-man game with him it is pretty easy to get opportunities open,” Mayfield said. “I kind of lucked out with two of them with him.”

Canisius struck first on a bouncer from a cutting Mathieu Boissonneault six minutes in, but Robert Morris responded with a seven-goal run to end the first half. The stretch started with strong transition play by the Colonials and was extended thanks to drawn out possessions. The Golden Griffins went without a sustained offensive set for a large chunk of the first half.

“We wanted to push as much as we possibly can when we had number advantages,” McMinn said. “Once those number advantages were exhausted, we really wanted to be patient. … We went into this game saying, ‘Hey when we do settle the ball down, let’s work to get set. … If we get shot clocks put on, that’s OK.’”

Canisius’ offense failed to find any rhythm, only stringing together two straight goals once. Golden Griffins leading scorer Connor Kearnan got three assists, enough to set a Metro Atlantic Athletic Conference record for single-season helpers, but was largely shut off by Robert Morris’ Zachary Bryant.

“We feel he’s one of the best there is to offer,” McMinn said of Bryant, the NEC Defensive Player of the Year. “I just challenged to Zach to step up like we have many times throughout the year.”

Kearnan finished his senior season with 52 assists and 83 points, setting new program single-season highs in both categories.

“It’s a great accomplishment, I’ll remember it, but I’d trade it to keep going and playing lacrosse right now,” Kearnan said.

Robert Morris got two-goal outings from Perkins and Shane Majewski. Canisius’ Boissonneault and Steven Coss both scored a pair as well.

Now, the Colonials turn their attention to the Terrapins, a team they haven’t beaten in two previous opportunities.

“We’re going to go into this weekend the same way that we do with any other game that we have,” McMinn said. “I’m proud of the fact that we’re here, but we still need to keep our head on straight.”