Jen Welter is believed to be the first woman appointed to a coaching role at an NFL franchise, after the Arizona Cardinals hired her.
The Arizona Cardinals have appointed who is believed to be the first woman coach in NFL history, with Jen Welter in charge of their inside linebackers in pre-season.
Welter, 37, already broke into the coaching ranks of a men's team in February when assuming the role of linebackers and special-teams coach at the Texas Revolution - a professional indoor American football team - and has now taken the plunge in the NFL.
Cardinals coach Bruce Arians said his reason for hiring Welter was simple.
"Coaching is nothing more than teaching," Arians said, according to the Cardinals' website.
"One thing I have learned from players is, 'How are you going to make me better? If you can make me better, I don't care if you're the Green Hornet, man, I'll listen'.
"I really believe she'll have a great opportunity with this internship through training camp to open some doors for her."
The NFL has been one leader in professional sports ranks to welcome women into a male-dominated space, with Sarah Thomas hired as the first full-time female official in April.
In the NBA, Becky Hammon took control of the San Antonio Spurs in the Summer League - helping them to the championship.
Elsewhere, Australian Rules football side St Kilda appointed Peta Searle as a development coach in 2014, while in football, Helena Costa was the first woman to coach a men's team in France - leading Clermont Foot.
Costa lasted less than a month, but Clermont - now in Ligue 2 - replaced her with Corinne Diacre.
In tennis, Spain appointed Gala Leon Garcia as captain of their Davis Cup outfit in September, but the appointment was not a popular one.
Similar to Clermont, Spain replaced Garcia with another former women's player Conchita Martinez, who was in charge of the side who lost a tie against Russia earlier in July.