LAS VEGAS – Joanna Jedrzejczyk is one of the world's best fighters, but first and foremost, she calls herself a wise businesswoman.

View photos Joanna Jedrzejczyk lands a blow against Valerie Letourneau at UFC 193 in November. (Getty) More

She had a sense for business, she says, from a very young age when she would work in her parents' small grocery store in Poland. Jedrzejczyk, 28, grins as she recalls them shooing her from the store, pleading with her to do something, anything else but spend hours toiling inside the store.

And with that, the fast-rising star and strawweight champion launches, unsolicited, into a full-throated defense of the UFC's pay scale. She was asked about her early struggles to survive, and begins to hack away at public sentiment that UFC fighters are underpaid.

It's not a position that's commonly held by the sport's fervent fan base, and a group of fighters has filed an antitrust suit against the company for that very reason.

"I hear people say Dana [White, the UFC president] and Lorenzo [Fertitta, its CEO] should pay the fighters better," Jedrzejczyk said. "But they don't know what they're talking about. They really take good care of us. All of us, you know? They [the fans] don't know anything about what is really going on.

"There are so many opportunities for all of the fighters. This is so different. You do your job and they'll take care of you. In Muay Thai, the female fighters didn't earn the same kind of money as [the men] despite doing the same job. But in UFC, all of us can earn good money, men and women. If you give 100 percent to the UFC, you'll get 200 percent back."

Jedrzejczyk, who has several lucrative fights ahead of her, including her next one that has yet to be scheduled against No. 1 contender Claudia Gadelha, has held her belt for only nine months. She won it with an upset in Dallas on March 14 at UFC 185 when she dominated Carla Esparza in Dallas and stopped her at 4:17 of the second round.

That was followed by a successful title defense over Jessica Penne in Germany in June and then one at UFC 193 in November over Valerie Letourneau.

Her non-stop attacking style has made her one of the promotion's fastest rising stars. She can barely walk more than 20 feet in the swank casino without someone calling out her name or pleading with her for a photograph.

"Love you, Joanna!" one 40-something man shouts, as she beams and nods her head. A young girl no more than 12 holds out her iPhone. Jedrzejczyk sees her and pauses for a moment, leans her head toward the child and grins as the girl snaps a selfie.

It's only a few years since her days as a struggling Muay Thai fighter, but a world of difference.

She has the money now to buy pretty much whatever she wants, which is a vast difference from how things were for most of her life, particularly as a young fighter trying to make her way.

She was fighting for a living, but as recently as five years ago, despite being a Muay Thai champion multiple times, she had to make choices that were excruciatingly difficult.

"I remember when I had just five Euros in my pocket, and I needed to buy a ticket [for the subway] to get to training," she said. "But I didn't know what to buy: Bread or the ticket. It wasn't both. One or the other."

She says that shoes – lots of them – are the one indulgence she's allowed herself as her financial lot in life has improved since she's become a UFC champion.

Story continues