Jen Welter walked from the sideline and shook hands with the line judge for the night's game between the Cardinals and Kansas City Chiefs.
This was no everyday meeting. More like a barrier-breaker.
Once a men's-only world, the NFL entered a new era Saturday night, when Welter became the first woman to coach an NFL game and Sarah Thomas became the first woman to work as a full-time on-field official.
More from FoxSports
This wasn't exactly new territory for Thomas. The 41-year-old had already worked NFL preseason games and training camp, including this year with a variety of teams. She also was the first woman to officiate in major college football and work a bowl game.
Saturday night's game was a little different because Thomas is now full-time official, a move that has generated plenty of attention in the male-dominated NFL.
Welter earned her place in the spotlight last month, when she was hired for a six-week internship as an inside linebackers coach for the Cardinals. She has earned praise from the Cardinals and coach Bruce Arians for her knowledge and go-all-time attitude during training camp, and will stay on through Arizona's four preseason games.
Welter played rugby at Boston College and spent 14 years as a linebacker, most with the Dallas Diamonds of the Women's Football Alliance, and won two gold medals with the U.S. team at the International Federation of American Football women's world championships.
She became the first woman to play a non-kicking position on a men's professional football team last year when she played running back and on special teams for the Texas Revolution of the Indoor Football League. Welter broke another barrier in February, becoming the first woman to coach for a men's professional team when the Revolution made her linebackers and special teams coach.
The NFL's gender breakthrough follows women's breakthroughs in the NBA.
Violet Palmer and Dee Kantner were hired as NBA officials in 1997, and last season Lauren Holtkamp became the league's third female official.
Becky Hammon became the NBA's first assistant coach with the San Antonio Spurs last season and the Sacramento Kings recently hired Nancy Lieberman, a Hall of Fame player, as an assistant coach under George Karl.