She's a Successful NFL Sports Agent. And, Yes, She's Ready to Show You the Money. Kelli Masters used to be a shy, insecure young woman. Then she took on the NFL and that male agent who told her, "Women will never make it in this industry."

When Kelli Masters walked into a Washington, D.C., ballroom in 2005 to take the National Football League's agent certification exam -- becoming one of the first women to do so -- she was clearly a, well, minority ("Three hundred men and me," she remembers of that day). Recognizing that fact, she recognized that she could let fear rule her emotions; she could focus on those ugly comments from naysayers, like "Why would you think you could be a football sports agent? You're a girl! You've never played football!"

But she had another option: She could steer her emotions in much more positive direction. As Masters related in a recent, powerful TEDx talk in Oklahoma City, "I closed my eyes and saw little boys playing on the playground or perhaps in their backyard. Perhaps they'd never touched a football or strapped on a helmet. But someday those little boys were going to need me to be prepared to walk through that process with them. ... they were going to need me to pass that [certification] test -- and I did."

Indeed, Masters, 45, already a successful litigator and law partner at that point, not only became the first woman to pass the certification test required to become an NFL agent (Hollywood's depictions of that line of work are "mostly true," she quipped), but in 2010 she became the first woman to represent a first-round pick in the NFL draft.

Not that things were a walk in the park getting there. Masters managed to sign her first client -- Cody Hodges, the quarterback from Texas Tech -- her first year, 2005, which, under NFL rules, allowed her to retain her agent's license. But she still encountered hostility: In 2006 she walked into her first NFL scouting combine -- the League's annual, pre-draft showcase of players -- and one of the game's most successful agents walked up to her with more than a dash of bravado. As Masters tells it, put he his finger in her face.

"What are you doing here?" he demanded. "Women will never make it in this industry. Everyone's going to laugh behind your back. Players will never respect you. Coaches, general managers are not going to listen to you ..."

Masters was ready. "Are you done?" she demanded back. "Let me tell you why you're wrong. You. Don't. Know. Me."

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Of course, along with the bullying and skepticism, there were the doubts of the clients themselves. "I would drive eight or nine hours for no-show meetings," Masters said at TEDx. "When I did get meetings, I would be told, usually by a dad or a mom or even a coach, 'We think you're qualified, Kelli, but we just don't think a woman can do this.'"

At least, Masters pointed, she had grown in confidence, executing a 180-degree turn from the self-conscious, always-trying-to-please young woman she had once been. Growing up in modest circumstances in Oklahoma City ("I still remember the green shag carpeting, the roaches in the sink"), she wanted desperately to somehow be part of the fast, fabulous world of football. To do that she became a national champion baton-twirler (performing at games alongside her baton-twirling twin sister). Later, she tried (twice) and ultimately succeeded in winning the Miss Oklahoma pageant, securing the scholarship that would pay for her law degree.

Despite these youthful accomplishments, Masters had little sense of self-worth. "I battled every single day for years for an opportunity for someone to believe in me," she said. "What if I had still been that person living her life, based on whether people approved?"

In fact, she left that person far behind, growing into an accomplished, respected NFL agent able to tout real success. So much so that during a recent dinner with several of her football player clients, she was finally able to close the circle and forever part ways with the insecure girl she'd once been.

As Masters tells it, she was engaged in light banter with the players when one asked how long she'd been an agent. Since 2005, she replied; then, on a whim, she presented her dinner guests with a question of her own: "How old were you all in 2005?"

"They looked at each other: '7, 8, 9 years old,' they replied," she said at the conclusion of her TEDx talk. And that answer, she said, made her suddenly realize: "Those were my little boys! They were the reason I took that test!"

Her circle of self-doubt, begun in that D.C. ballroom testing site in 2005, had finally closed.

In an email Q&A, Masters told Entrepreneur even more about her nontraditional career:

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What name players have you represented?

"My first drafted client was Gerald McCoy, drafted No. 3 overall by the Tampa Bay Buccaneers in 2010. While I no longer represent Gerald, I've gone on to represent many other drafted players, including Quinton Carter (drafted by the Denver Broncos, now retired), Jordan Phillips (drafted by the Miami Dolphins, now in Buffalo) and David Moore (Seattle Seahawks). But some of my most accomplished players were undrafted, including Blake Jarwin (Dallas Cowboys) and Tress Way (Washington Redskins)."

As a woman entrepreneur in a traditionally male job, what have you learned?

"Not all advice is good advice. I've been blessed with great mentors, but I've also learned how important it is to be true to myself. Before I pursued certification as a sports agent, I spent more than a year researching and soul searching. When I did become an agent, I knew what I was meant to do, and that has anchored me during many storms. Early on in the business, I observed how other agents approached recruiting and representation and learned what to do, and what not to do. I also determined to never compromise my values or take short cuts, no matter how enticing it may look.

"As I tell young people all the time, it actually is what you know and who you know. In spite of every challenge and every setback, I have stayed grateful and am living a meaningful life because it is founded on principles and being good to people. To me, that is true success."

What kind of advice can you offer to other women pursuing nontraditional careers?

"When I first became a certified sports agent, I was given some advice by a woman whom I admired who came from the legal field as well as politics. She told me, 'Kelli, you're going to have to work twice as hard to be thought half as good.' She was right. This presents women with the crossroads. How do you want to take that truth in? Instead of getting discouraged or defensive, I decided I would outwork my competition while maintaining the highest levels of integrity and excellence possible. I also chose to make my differences strengths and see them as such.

"I still fight many of the stereotypes: 'Women are too emotional.' 'Women are too weak.' 'Women can't succeed in male-dominated industries." That is inaccurate and the opposite of the truth. In my role as an agent, as a woman, I offer fierce advocacy, protective instincts and the ability to get things done in a way that is often more efficient and effective than [what you see with] many of my male counterparts.

"So my advice to women is this: Dig deep, press in to know your purpose and pursue it with passion. Be confident and carry yourself professionally. Realize that what makes you different makes you better. Also understand the importance of educating others and building alliances, both with men and with other women. We need each other in order to be successful. But no matter what, don't let anyone tell you what you can't do simply because of your gender. "