Joanna Jedrzejczyk takes a more positive approach to her rematch with Rose Namajunas

Looking back on her first loss in the UFC, former women’s strawweight champion Joanna Jedrzejczyk insists she didn’t dwell on it for very long.

“I don’t know if you’re going to believe me or not, but I got over it the same night,” Jedrzejczyk said of her first-round knockout loss to Rose Namajunas in November.

“I went to the locker room, and I had brought my nephew there. He was 7. It was his first fight. I saw him and he hugged me — ‘Hey, auntie, you must be so sad’ — but I had to be so strong for this little kid. I must show him how to deal with losing in life, to be an adult, to be very strong.”

Saturday night in the co-main event at Brooklyn’s Barclays Center, Poland’s Jedrzejczyk (14-1) and Colorado’s Namajunas (8-3) meet again.

The event has been deeply overshadowed by men’s lightweight champion Conor McGregor, who faces criminal charges after going on a post-media-day rampage in response to Russian Khabib Nurmagomedov’s likely assumption of a belt being stripped from McGregor for inactivity.

Jedrzejczyk’s journey here is all about coming to terms with the loss.

“People wanted me to hide from this. No, I want to show them something,” she said. “I lost fighting, and fighting is my job … but there’s still so many things in my life that will happen – good and bad – in my future.

“What I know is that I want to give power to people who have failed and don’t have enough energy and strength to rise. I want to say to them that it doesn’t matter if you are a businessman or an athlete, or had something bad happen in your life, and you don’t feel like you want to go through it. I want to say, ‘Guys, it’s worth it. Life is too short and beautiful to wait for a great moment. Take life in your hands and go for it.’ This is what I want to show.”

Jedrzejczyk acknowledges that she came across as a bully in the first fight against Namajunas. The then-champion pressed her fist to Namajunas’ nose at a promotional faceoff and also said some heated things that were picked up by hot microphones.

It seemed out of character.

She blames some of that prefight behavior on “mental stuff” promoted by Namajunas’ fiance and coach, Pat Barry.

“I’m not a [psychological] person. I know what they’re saying, that I’m a bully, that I’m hating,” Jedrzejczyk said. “I know Pat Barry said, ‘We wanted to make her look bad, she’s a bad person.’ Come on, guys. To do that, shame on you, not on me. I’m such a positive person. I’m real, not fake. If I have to show that emotion, I will show it. I will not play with you. People only show one side of the battle. They didn’t show the reason, but it’s [the] past. I’m a different person now.”

Part of that, she says, is rooted in the careful approach she and her coaches took for this weight cut after the one in November, when Jedrzejczyk said she had to drop an estimated 15 pounds in the 14 hours before her loss to Namajunas.

“Last time I was a different competitor,” she said. “I know why I got knocked out. Rose is a good fighter. She hits precise, but my body couldn’t take it.

“People who didn’t go through the weight cut will say it’s an excuse. I didn’t say that, but it wasn’t me. My brain was frozen. I was not a competitor that night. How do people want me to be the best person in the octagon when my body was not there? I went through the weight cut and walked to the octagon for the people who came there and bought the pay-per-view … I did it for them. How can I say I can’t [fight]?”

Her commitment to martial arts is fierce. She resides away from her Polish fiance for several months a year while training in Florida and recalls a Christmas morning on a fight trip to Thailand where she broke down in tears because she was so alone.

“You can look only at my last fight if you want to, but I’ve been doing this for 15 years, almost 100 fights. I cut my teeth on this sport,” Jedrzejczyk said. “I will show up in the best shape ever, and I will take over the show.”

lance.pugmire@latimes.com

Twitter: @latimespugmire