Charlestown’s Reagan O’Brien, a star defender at Johns Hopkins, one of five finalists for the Tewaaraton Award

Reagan O’Brien is proud to be “making defense cool again.”

A senior defender at Johns Hopkins, O’Brien — who hails from Charlestown and graduated from Boston Latin in 2022 — leads the nation in caused turnovers (75) and holds the NCAA career record (241 and counting). Last season, she set the NCAA record for a season with 103.

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The Big Ten Defender of the Year in two consecutive seasons was named a finalist for the 2026 Tewaaraton Award, given annually to the nation’s top women’s lacrosse player, and this season she led Johns Hopkins to its first Final Four appearance in the program’s 50-year history.

“She has really, truly, in my eyes changed the game of lacrosse from a defensive standpoint,” said Johns Hopkins coach Tim McCormack, who noted that opponents hesitate to carry the ball into O’Brien’s area of the field, knowing that she’ll likely force the ball out of their stick.

In Ja recent third-round NCAA Tournament game against Stony Brook, the Blue Jays trailed by a goal with 1:30 on the clock, and O’Brien forced turnovers that led to goals on consecutive possessions to give Johns Hopkins a regulation win and a spot in the Final Four.

In the midst of their best season, the Blue Jays (17-4), will face top-ranked Northwestern (17-3) on Friday at 5:30 p.m. (ESPNU) in Evanston, Ill., for a spot in the national championship game. The Tewaaraton will be awarded the following Thursday at a ceremony in Washington.

“What makes me really excited about it is little kids who have always looked up to attackers and midfielders can look up to defenders, too,” O’Brien said.

That she’s one of five finalists for the Tewaaraton Award is even more impressive given a defender hasn’t been named a finalist since 2021, and only 17 defenders have been among the finalists in the award’s 25-year history.

“That alone shows you the impact she’s had on the sport,” McCormack said. “The success that we’ve had is a direct correlation to what she’s done here.”

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McCormack has known O’Brien and her older sister, Quinlan, for more than a decade since meeting the pair at recruiting camps in the Boston area. When he took over at Johns Hopkins in 2022, just before O’Brien’s freshman year, McCormack was thrilled to see her name on the roster.

“She’s a killer, she’s unbelievable, and she has been since back then,” McCormack said. “The best thing has been watching her grow, watching her mature over those years.”

McCormack said O’Brien’s stats are enough to earn her the Tewaaraton Award, though her impact on the rest of the program has had a ripple effect larger than what’s visible in box scores.

Aggressive defense is a hallmark of her game, though her success in forcing turnovers is not exclusively a result of physical play and hard checking. She’s adept at reading attackers’ body language, is quick to cut off their angles, and appears seemingly out of nowhere to hawk balls out of the air.

Second-team and scout-team players at Johns Hopkins request film sessions dedicated to breaking down O’Brien’s game. Girls in the stands zero in on her, and McCormack has even seen opponents try to copy her defensive style.

“Her impact on a day-to-day basis is really unseen,” McCormack said. “What it does to the girls who help prepare our defense … they are being pushed every single day by her ability to compete.”

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