SAN ANTONIO, Texas -- Senior Nate Bascom became Ohio Northern's all-time single season assist leader as Ohio Northern topped Susquehanna 4-1 on Saturday in the third round of the NCAA tournament.

The Polar Bears improved to 23-2 on the season, while the Crusaders finish their season at 18-3-1.

Northern advanced to the quarterfinals for the second time in school history and will play on Sunday.

Bascom recorded his record-breaking 15th assist this season for OSU.

Freshman Keegan Ross also scored two goals, which gives him 22 on the season and ties a single-season school record.

The Crusaders struck first in the 16th minute, when they took a corner kick that bounced around the box before Brandon Kates knocked it in.

Northern responded at the 20:04 mark when Bascom took a shot that hit the post and deflected back out. Ross was right there to score his 21st goal of the season off of the rebound.

The Polar Bears would need less than two minutes to claim the lead at 2-1. Bascom dribbled down the left side and found senior Cameron Johnson, who buried his shot in the back of the net at the 21:53 mark.

"This was the second game in a row where our opponents scored first," head coach Brent Ridenour said. "Our guys did not put their heads down. They battled back and were able to get us a lead heading into the half."

Freshman Shintaroh Itoh had a chance to score in the closing moments of the first half, but his shot was saved by Crusader goalie Matt Salsman.

Itoh then sent another shot from just outside of the box in the 51st minute, but Salsman again made the save.

The Crusaders had a chance to score when they took another corner kick and Patrick Fry headed a shot that senior goalkeeper Mac Church tipped over the crossbar.

Northern expanded their lead at the 54:05 mark, when senior Chris Matejka took a corner kick and found senior Austin Windsor, who shot a bending ball into the top left corner, putting ONU up 3-1.

Susquehanna also had an opportunity in the 59th minute, but Andrew Hayes' shot hit the crossbar.

The Polar Bears missed a chance in the 63rd minute when Ross fired a shot that was stopped and the rebound shot attempt by junior Stephen Perkins was saved.

Northern put the game away when sophomore Chuck D'Imperio fed a ball into the box that Ross headed past the goalie at the 79:37 mark, giving Northern the 4-1 lead.

Church made two saves and improved to 23-2 on the year.

Salsman made four saves in goal and fell to 18-3-1.

"Susquehanna is a tough defensive team," Ridenour said. "To score four goals on them says a lot about the ability of our offense. I am very proud of the guys and we look forward to being back in the quarterfinals."

The Polar Bears outshot the Crusaders by a 23-20 margin and had an 11-3 advantage in shots on goal.