The CEO of the Dallas Mavericks has achieved that and more—landing her latest role off the back of a cold call from Shark Tank star Mark Cuban.

In an interview with LinkedIn CEO Ryan Roslansky, Marshall discussed her 30 years at telecommunications company AT&T, where from 1981 onward she worked variously as a recruiter, network engineer, and chief diversity officer.

Following a battle with stage 3 colon cancer, in 2017 Marshall retired from the Dallas-based company to launch her own consultancy brand helping businesses transform their company culture.

Yet when it was barely off the ground, she got a phone call from an unknown number. Mark Cuban was on the other end of the line.

He asked her to become CEO of his basketball team, the Dallas Mavericks, which he purchased in 2000 for $285 million.

“I thought twice about it,” Marshall admitted. “I was loving what I was doing with the consulting, but here was an opportunity to serve, to have an impact.”

The telecoms executive said she was well aware she didn’t “know the business of basketball,” but Cuban was undeterred.

“You don’t worry about that,” Cuban, who is worth approximately $5 billion, told her. “I will teach you the business side of basketball and others will do the same.”

Marshall admitted she became “more and more aware” of the gaps in her knowledge as she spent more time at the club, but said Cuban kept his promise to teach her.

“I had to dig in and learn which I love,” the first female CEO of the Mavs said. “Some of the gaps still exist, I will never know what some of these people know about the business of basketball—but I don’t need to know it. I learn from it every day.

“What I need to do is lead these people, learn from these people and love these people. And I try to do that every day.”

Lead by the first black woman CEO of an NBA team, around 50% of the Mavericks’ staff are now women and nearly half are people of color.

The club was recently awarded the league’s Inclusion Leadership award, flying in the face of headlines in the past about harassment at the organization.

Turning down promotions

Marshall also revealed she has turned down a total of four promotions in her career, saying she always asks two questions about a new role—if the answers don’t satisfy, she doesn’t take the offer.

Those questions are: “What is it that I have to do in this job? Because whatever it is, I want to deliver above and beyond.”

The second is “Who is it that you want me to touch? I always believe that I am in a position for a reason and if I get a good sense and if I get a good sense that I’m doing something that adds value to the business and that I’m going to be a blessing, I’m ready to go.”

Marshall continued she initially turned down the “biggest promotion of her career” 20 years into her stint at AT&T—which has been named among Fortune’s 100 Best Companies to Work For in the past—because she was being asked to change who she was.

After she was approached to become one of the officers at the company, Marshall’s boss handed her a magazine of what to wear and was told her name of Cynt would have to go—she would be Cynthia or Cindy.

In short, Marshall said, her boss didn’t believe Marshall was “sophisticated enough to be an officer.”

Perhaps unsurprisingly, Marshall turned the offer down, telling her boss: “I’m flattered but you’re fundamentally asking me to change who I am.”

Marshall said she later received a call from the chairman of the company, though she didn’t name him, who told her: “The person the board has signed off on to be an officer is Cynt, and that’s who we want to walk in to our doors tomorrow.”