She seemed to do her job, which ended by helping to separate St. Louis Rams and Detroit Lions players after some shoving, pushing and shouting broke out following the final play.
Eastin became the first woman to be an official in an NFL regular-season game, working as the line judge in the Rams-Lions matchup Sunday.
"It's a great milestone," Detroit coach Jim Schwartz said after his team beat St. Louis 27-23. "But we didn't think about it all during the game."
That's probably just the way she — and the league — liked it.
Eastin is among the replacement officials hired by the league while the regular officials are locked out. Replacement officials are working games for the first time in 11 years.
She became the first female official to work an NFL preseason game last month as the line judge when Green Bay played at San Diego. The Pro Football Hall of Fame has the hat and whistle she used during that preseason game, and they'll are expected to be displayed in Canton, Ohio.
The 42-year-old resident of Tempe, Ariz. has worked as a referee in the Mid-Eastern Athletic Conference — college football's second-highest level — and has 16 years of officiating experience. MEAC officials declined comment on Eastin, as did the NFL in the days leading up to the groundbreaking assignment.
"Commenting on individual officials is not something we do," league spokesman Greg Aiello wrote in an email. "Her place in league history speaks for itself."
NFL Commissioner Roger Goodell has said having Eastin on the field is a great opportunity for her and the league.
"She's well prepared for it, and I think she'll do terrific," Goodell said last month. "So we're excited about that.
"And there are more coming, by the way. We've been working along this path to try to properly train and prepare a female official, and now we have the opportunity."
The NFL declined to make Eastin available for interviews during the week leading up to the game and didn't allow media to have access to her following the Rams-Lions game, but did set up a conference call with her in August.
"I hope to show it really doesn't matter if you are male or female," Eastin said last month.
Eastin walked onto the Ford Field turf about 50 minutes before kickoff Sunday, chatted briefly with a police officer and shook hands with Lions linebackers coach Matt Burke. She then went largely unnoticed as she paced the home team's sideline during pregame warm-ups.
Pittsburgh Steelers linebacker Larry Foote believes it is good for the game to have female officials, even though he worries about her safety working alongside some of the world's biggest, strongest and fastest athletes.
"Women are more honest and fair than men and they know how to catch a man cheating," Foote said. "I hope she's just a line judge. Don't want her to get hurt."
Eastin, who is originally from Worcester, Mass., was a multiple national judo champion as a child and started officiating high school games before moving up to colleges. She owns a company called SE Sports Officiating, which trains officials in football and basketball.
"I'll be working even harder, to show I am capable and I am where I should be," Eastin has said.
She is joining a small group of women to break into officiating ranks at the highest levels of sports.
"It's a sign of the times," Lions centre Dominic Raiola said. "The NBA did it."
Violet Palmer, one of Eastin's inspirations, started officiating NBA games in 1997 and is still in the league. Bernice Gera became the first woman to work in baseball's minor leagues in 1972 as an umpire in a New York-Penn League game. Pam Postema umpired major league spring training games in 1989 and Triple-A baseball for six seasons.
The locked-out NFL Referees Association has said Eastin shouldn't be allowed to work league games because she has been in the World Series of Poker. If Eastin is hired permanently, the NFL's gambling policy would bar her from participating in such events.
Basketball Hall of Famer Nancy Lieberman, the first woman to play and coach against men in professional basketball, is glad the NFL's labour problems with its regular officials opened a door for Eastin.
"She doesn't have to hit anybody, she just has to know the rules," Lieberman said. "She won't be defined by her gender if she does her job. And while this is not normal for the rest of the world to see, this is very normal for her because she works as an official for a living."
Kathy Babiak, co-director of SHARP, a partnership between the Women's Sports Foundation and the University of Michigan, said Eastin's accomplishment is encouraging.
"It shows the strides women and girls in sports have been making since Title IX was passed 40 years ago," Babiak said. "Before Title IX, these kinds of opportunities for women and girls were not even imaginable. It shows that women and girls have a desire, interest and ability to work in sports at all levels — even men's professional sports.
"Some girl will be watching Sunday and say, 'Hey, I want to do the same thing!'"
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