Last year Shannon Eastin made history when she became the first woman to serve as a referee in an NFL game.

And while Eastin's breakthrough was somewhat unexpected and unique -- she was serving as a replacement referee while the NFL owners were locking out the regular officials -- it may not be long before the league has its first woman serving as a full-time official.

The Associated Press reported recently that Sarah Thomas, currently a Conference USA referee, will join the Indianapolis Colts' training camp next month as part of the NFL's officiating development program. She may even call some preseason games this year.

Once Thomas finishes the officiating development program, she could be selected as a full-time referee. For that to happen, a current referee would have to retire or leave the league, thereby opening up a spot.

Dean Blandino, the NFL's vice president of officiating, told the Associated Press that Thomas has been "in the pipeline" for a while, and it will be important for her to adjust to the quicker tempo of NFL games.

"It's similar from when a players jumps from college to the NFL," Blandino said. "Getting used to that type of speed is important."

Thomas will also have to pass the standard interviews, background checks and evaluations by the NFL during camps, preseason games and college games that she works.

If and when she becomes a full-time referee, Thomas will follow in the footsteps of the NBA's Violet Palmer, the first female official in any major North American sport.