The saying in corporate America goes that a hundred attaboys get wiped out by a single “Oh, no!” Sometimes, that adage applies equally well in hockey.

Not tonight.

Massachuetts-Lowell suffered two major “Oh, no!” mistakes, but put together enough attaboys to upset Boston University, 3-2.

The River Hawks’ first major mistake came after Joe Gambardella staked them to a 1-0 lead just 1:35 into the game. Less than two minutes later, however, BU tied the game off a horrible Lowell turnover in the defensive slot.

The River Hawks’ penalty kill earned a host of attaboys at the end of the period when it killed off a 1:30 five-on-three disadvantage, not even allowing a shot in the process.

Those attaboys, however, went up in smoke with an “Oh, no!” mistake of epic proportions. Enjoying a five-on-three of their own, they allowed a Bobo Carpenter breakaway and short-handed goal.

In corporate American, an “Oh, no!” of that magnitude can result in a quick ushering to the door, a shove outside, and loud slamming of the door behind you.

Not so with Lowell coach Norm Bazin’s River Hawks.

“Those things happen,” said Kenny Hausinger, who would eventually score the game-winner in the third. “It’s hockey. We had the two bad bounces, but we put them behind us and got back to work.”

But a five-on-three short-handed goal? Isn’t that such a whopper of a blunder that players, the wind taken out of their sales, can’t put it behind themselves?

“I knew miscues would happen,” Bazin said. “We don’t try to not make mistakes. We try to generate chances. If you generate enough chances, you make up for the mistakes.”

Lowell began doing exactly that. Ryan Lohin scored at the 11:05 mark, and the two sides went into the second intermission tied, 2-2.

In the third, BU got the first of two power plays, but again couldn’t solve Lowell’s penalty kill. And when the Terriers made the mistake of committing a trip deep in the offensive zone, Lowell made them pay, getting Hausinger’s game-winner.

“Our power play is really struggling,” BU coach David Quinn said. “When you look at the talent out there, it’s a head-scratcher. If we’re going to go anywhere, we’ve got to be much, much better on the power play.

“We couldn’t even muster a shot. They got a power play and looked like the Harlem Globetrotters and got a goal.”

In the end, that power-play goal and Lowell’s perfect 0-for-5 penalty kill, during which it allowed only four shots, provided the attaboys necessary to knock of the number three team in the country.

Hockey East roundup

Merrimack 6, at No. 7 Boston College 3
Led by Hampus Gustafsson’s hat trick, Merrimack stunned Boston College, Hockey East’s top team in the standings. In doing so, the Warriors finished the season 3-0-1 against BC and BU, the top two teams in the league, while ironically going 2-7-4 against the others.

No. 16 Notre Dame 3, at Maine 2
Notre Dame seized a 3-0 lead after two periods on goals by Jack Jenkins, Anders Bjork, and Andrew Oglevie. Maine rallied with two third-period goals, but the second came with an extra attacker with only four seconds remaining, making the 3-2 margin appear closer than it really was.

No. 11 Providence 4, Connecticut 3
Despite outshooting UConn, 52-18, Providence had to rally twice from deficits and didn’t get the game-winner off the stick of Erik Foley until 13:04 of the third period. It was the Friars’ second power-play goal of the game to one for UConn.

New Hampshire 4, at No. 15 Vermont 2
UNH upset Vermont in its own barn, 4-2, coming from behind with three goals in the third period. Tyler Kelleher scored twice. The loss knocked the Catamounts all the way down to 20th in the PairWise, outside of the NCAA tournament selection bubble.

Northeastern 6, Massachusetts 2
Northeastern seized a 4-0 first-period lead, then responded to two UMass goals with a short-hander and its second power-play goal of the game. Nolan Stevens and Zach Aston-Reese each scored twice.