BUFFALO, N.Y. — Competing in lacrosse, swimming and bowling in high school wasn’t enough for Kathryn Smith.

Come fall, she would spend most Friday nights on the football sideline helping her father, Robert, track statistics for Christian Brothers Academy in Syracuse.

Little did anyone envision that some 15 years later Smith’s passion for sports would lead her to become the NFL’s first full-time female assistant coach.

“That’s just her nature, that whatever she’s doing, she’s certainly going to jump in head first,” Christian Brothers athletic director John Wleklinski said Thursday.

“She goes from being someone hard-working, doing the right stuff, to all of a sudden being the answer to a trivia question. And it couldn’t happen to a nicer person,” Wleklinski added.

Wleklinski spoke fondly of Smith a day after Coach Rex Ryan and the Buffalo Bills broke a gender barrier by promoting the 30-year-old to be their special teams quality control coach.

“I appreciate Rex Ryan giving me this opportunity based on the merit of my work and commitment to this organization,” Smith said, in statements released by the team. “The amount of attention generated in the past 24 hours has been extraordinary. However, my focus remains on my job responsibilities and helping the team win.”

She has 12 seasons of NFL experience, starting in various internships with the Jets.

And she got her coaching break because of Ryan, who recognized Smith’s potential when he was hired as Jets coach in 2009. Ryan brought Smith with him to Buffalo, and she spent this season as an administrative assistant for the Bills’ assistant coaches.

“Kathryn has been a part of Rex’s staff for the past seven years and has proven that she does excellent work,” Bills co-owner Kim Pegula said in a statement. “While we understand the significance of this announcement, it’s important to understand that Kathryn earned this position because she has shown she is qualified, dedicated and puts in the work needed for this role.”