College football official Sarah Thomas has been officiating at the New Orleans Saints' training camp as she edges closer to becoming the NFL's first female referee.

Thomas, who became the first woman to officiate a college bowl game, is in the advanced stages of the NFL's officiating development program.

She told the Saints' official website: "I'm an official, and that's what I like about it. I've been [in New Orleans' camp] before so I'm not so much of a novelty. Really and truly, you're an official out there and that's how I'm perceived.

"The professional level, they're just amazing, gifted athletes. You've got a tremendous amount of speed and athleticism. But the college level when you're out there, they're great athletes as well. The speed is probably the greatest difference."

Saints tackle Zach Strief added: "She's been here several years in a row and you kind of see, I think, her confidence grow. And it's gotten to a point where, yes, it's another one of the officials. Clearly, she's extremely knowledgeable on the game and that shows and more than anything, it's great for the league to show that kind of diversity and open up that field for anybody."

Thomas could officiate in the NFL as early as 2014.