A week ago, the Harvard women’s lacrosse team called on its offense, and its attackers responded in style, firing home 21 goals in a rout of St. Mary’s. This weekend, it was the defense’s turn to lead the Crimson.

Harvard (3-1, 1-0 Ivy) opened Ancient Eight play in New York this Saturday with a 15-6 win over Columbia (1-2, 0-1). Although the Crimson offense was productive once again, it was a determined display from the backfield unit that secured the victory, as the defense held the Lions to their lowest goals total in the matchup since 2012.

“The defense was disruptive,” Harvard coach Lisa Miller said. “They never let Columbia get comfortable or establish a rhythm.”

Harvard entered the game ranked in the top 20 in the country for scoring defense, and the backfield unit lived up to its billing against the Lions. Co-captain and goalie Kelly Weis led the defensive effort, tallying seven saves, while junior midfielder Meghan Hennessey took control of the outfield, picking up a game-high six ground balls and forcing three turnovers.

“Megan played incredibly well on the defensive side of the ball,” co-captain and midfielder Audrey Todd said. “She lit a spark on defense and made the offense want to capitalize on her impressive play once the ball transitioned down the field.”

Despite an increased focus on the backfield, the Crimson, boasting the 17th-best scoring offense in the nation, did not disappoint on attack. The win marked the third game this season in which Harvard totaled 15 or more goals, and nine different Crimson players found the back of the net on the day.

“The team played like a complete unit today,” sophomore midfielder Glynn said. “It began with the stops on the defensive side and ended with finishing by the offensive unit. The energy from the defense made the attack want to capitalize on their great play.”

Spearheading the potent Harvard offense was junior attacker Marisa Romeo. The Syracuse, N.Y., native picked up an assist and notched a game-high four goals, taking her season total to 10. Glynn also continued her run of impressive performances, setting up three goals and scoring one of her own over the course of the afternoon.

The Crimson’s formidable attacking unit wasted no time in making its presence felt, as Romeo put the team on the scoreboard with her first goal of the afternoon a mere 41 seconds after the whistle. Junior attacker Maeve McMahon and freshman midfielder Keeley MacAfee added to Harvard’s momentum shortly afterwards, scoring less than a minute apart to put the Crimson ahead, 3-0.

Columbia found the back of the net twice to bring the score within one, but the Harvard backfield recovered, holding the Lions scoreless for the remainder of the half, while the Crimson attack exploded for a flurry of points.

Sophomore attacker Eliza Guild tallied two goals, and senior midfielder Alexis Nicolia collected one of her own before McMahon and Glynn each found the back of the net.

Romeo then picked up two more quick goals in the final five minutes of the first half to cap a 7-0 run and put Harvard ahead, 10-2, at the whistle.

Both the Crimson’s offensive and defensive units continued to shine in the second period.

Nicolia would score again shortly after the restart to stretch Harvard’s advantage to nine, and the Crimson defense kept Columbia off the board until nine minutes into the second half. In total, Harvard held the Lions scoreless for over 30 minutes between Columbia’s second and third goals.

While the back line continued to hold firm, the Crimson offense kept the contest out of reach for the Lions. Romeo would find the back of the Columbia net for the fourth time with 20 minutes left in the second half before providing the assist for a goal from Todd just 16 seconds later.

Tallies from Hennessey and senior attacker Meghan Bauer sealed the victory and pushed Harvard’s run of wins against Columbia to seven-straight. The win also extended the Crimson’s record against the Lions in New York to a perfect 9-0.

“The bottom line is that we did our job out on the field today,” Todd said. “We knew Columbia would give us a good fight, and we did a great job of making sure we set the pace of the game on offense and played solid defense on the opposite end of the field.”

—Staff writer Sam O.M. Christenfeld can be reached at schristenfeld@college.harvard.edu.