Ronda Rousey's next opponent only started training in MMA four years ago in an attempt to lose weight

Four years ago, Bethe Correia was a newly-married accounting student who had never trained in MMA. Now, she's set to take on one of the most feared fighters in the world when she Ronda Rousey square off to headline UFC 190 this Friday.

It's a dramatic leap, one that few - including Correia - could have predicted.

Yahoo Sports Kevin Iole calls Correia, "one of the most unlikely UFC title challengers ever." It would be very hard to dispute that claim. The 5' 5" Brazilian may be one of the top UFC fighters now, with an undefeated 9-0 record, but, in 2011 Correia had no real MMA and fighting experience.

In fact, Correia told Ozy's Shannon Sims she initially had no plans to try to compete professionally when she first started training. She joked she only picked up the sport because she "started getting fat, like all women do after they marry."

It wasn't until a random chance encounter with current Bellator Featherweight Champion Patricio Freire, at a gym in Natal, Brazil, that she started to take her training seriously. Freire told Sims he remembers being on the opposite end of the gym and hearing someone laying a beating on a punching bag, so he went out to see who it was. He was shocked to find out it was a young woman delivering the powerful blows.

"I came in to see who was hitting it so hard," Freire said. "And when I saw it was this out-of-shape, regular-looking woman, I just stopped in my tracks."

Freire convinced Correia to try out MMA at his personal gym nearby. Four years later she's still training at the same gym, except now for a title fight.

Despite the feel-good story, Correia remains a heavy underdog in her upcoming fight. Rousey opened as a 15:1 favorite, and nearly all experts expect another win - with many predicted it to come as early as the opening minutes of the first round.

Correia, however, told Iole she remains confident she'll give Rousey, who owns an undefeated 11-0 record, her first loss.

"Ronda is a very good athlete and she has accomplished a lot," Correia said. "But she's not the only one. I feel I have the style, the total game, to be the one to beat her. And so it doesn't matter if it is one, two or 10 times. I'll fight her and beat her as much as I have to to show who is the best."