The No. 3 seed Boston University men’s lacrosse team may have entered the Patriot League quarterfinal as postseason rookies, but it did not appear as such on Wednesday night.

Behind seven combined goals from sophomore attacker James Burr and senior midfielder Cal Dearth, the Terriers (12-3, 5-3 Patriot League) shut down No. 6 seed Lehigh University in a 10-4 shellacking.

BU began to separate themselves from Lehigh (7-7, 4-4 Patriot League) in the third quarter as the offensive attackers started to match the effectiveness of the defensive unit.

Immediately from the outset of the period, the Terriers were the aggressors. The scoring barrage began with 12:33 remaining in the third quarter, as Burr caught a feed from freshman midfielder John MacLean on a cut and whipped it into the goal for a go-ahead tally.

“We were a little bit nervous in the beginning, but we were able to just make some plays,” said BU head coach Ryan Polley. “We made some really tough plays in the second half. I was most proud of that.”

A brilliant feed from Dearth to junior attacker Ryan Hilburn in the middle of the Mountain Hawks’ defensive zone led to a conversion by Hilburn with 6:15 left. Then, Dearth ripped a high shot past the weak side of Lehigh sophomore goalkeeper Chris Kiernan to give the Terriers a three-goal advantage with just over four minutes left in the quarter.

Dearth is third in goals per game in the Patriot League and averages 2.33 per night. The veteran player was as effective as ever in his postseason debut, notching three goals and two assists for a five-point night.

“We knew we had them,” Burr said. “We knew we were a better team than them. We had some turnovers on offense, but we came out with energy and we executed a little bit better [in the third quarter]. Our defense was absolutely stellar. They just held it down and opened up looks for the offense.”

With just 91 seconds to go in the third stanza, MacLean caught a cross-field pass on the right side of the cage, which bounced underneath the net to increase BU’s lead to four goals at the conclusion of the third.

For those that were doubting if Burr could match the four-goal explosion he mustered in the 12-11 victory over the College of the Holy Cross, he eased their concerns by rattling home four goals for the third time this season, providing the Terriers with a reliable finisher.

“Credit to [the coaches] for putting in a new offense for every game,” Burr said. “We were playing at a fast pace, and our looks were open because of that.”

Burr first placed BU on the board with 9:37 remaining in the first quarter, erasing an early one-goal deficit after corralling a feed from sophomore attacker Michael Laviano.

In the final 15 minutes, Burr collected the hat trick after converting on a Hilburn assist with 7:48 in the fourth quarter before putting home another two minutes later on an empty net to give the Terriers a convincing 9-3 lead.

On the other end of the field, the Terriers’ defense further propelled them to victory.

Lehigh entered the contest averaging 9.79 goals a night while also boasting the league’s leading goal scorer in sophomore attacker and midfielder Andrew Pettit. However, the Terriers defensive approach left Pettit scoreless for the contest.

“[The defense was] playing incredible,” said senior goalkeeper Christian Carson-Banister, who made 11 saves. “The best thing about tonight was our slides and recovery and locking up on the inside. They played great when we needed to slide or we had a fill, which is awesome. [Lehigh] could not get anything going.”

Senior long-stick midfielder Greg Wozniak was instrumental in helping BU force 23 turnovers, causing a trio of turnovers himself, while sophomore defenseman Quintin Germain forced two.

“Wozniak was the best player on the field,” Polley said. “He was everywhere. He was really disruptive to the Lehigh offense. We did a great job on [Pettit].”