Bellator 297: Stopping history-chasing Pitbull a chance to build my legacy - Sergio Pettis

Before Sergio Pettis' serious knee injury, he was enjoying the most productive run of his career.

On a five-fight win streak, the American had just defended his Bellator bantamweight title, stopping Kyoji Horiguchi with a spectacular spinning backfist and earning the promotion's knockout of the year award.

"I was making some really good money. I was definitely changing," Pettis told BBC Sport.

"I was thinking 'what can I buy next? Can I get this new car? Can I get this new piece of jewellery? What can I buy my fiancee?"

Pettis was preparing to face Raufeon Stots in the quarter-finals of Bellator's Bantamweight Grand Prix, with the eventual winner claiming a $1m (£800,000) prize.

Pettis, 29, describes the sum as "life-changing", but while grappling during his training camp for the bout, the opportunity to claim the prize evaporated when he suffered a torn anterior cruciate ligament.

The injury resulted in the longest lay-off of Pettis' career, but on Friday he returns to action after over 18 months out when he defends his belt against Brazil's Patricio 'Pitbull' Freire at Bellator 297 at the Wintrust Arena in Chicago, Illinois.

Featherweight champion and former lightweight title holder Freire, 35, is attempting to become the first ever three-division champion in a major MMA promotion, but for Pettis it's a golden opportunity to refocus.

"I think last year was the universe teaching me how to stay true to my goal. I promised myself coming into this sport I wouldn't be doing it just for the money," said Pettis.

"It was an eye-opener in a way. To really focus on the legacy - I want to make sure that Sergio Pettis has some history to leave behind.

"Now I get to fight for legacy. Fighting against Patricio, who is chasing the three-time division champion, and I'm going to be the man to stop it."

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'I was a demon at times, but I grew a lot during time off'

Pettis (left) will be taking part in his fifth Bellator bout, compared to Freire's 28th

The injury represented the biggest setback of Pettis' career so far, with the former UFC star revealing he had never required surgery prior to it.

Unable to train for a long time, Pettis' weight rose to 13 stone (82.5kg, 182 pounds), which is just three off the middleweight limit of 13st 3lb (84.1kg), four divisions heavier.

"For the first couple of months it was depressing. I couldn't move, I couldn't do the things I used to do - I like to go out in nature, go for walks and go fishing," said Pettis.

"Last summer I was at home all day, every day. I'm sure my dogs enjoyed that but it was definitely a whole different year for me.

"My lady was putting up with a demon. I was constantly mad. Mad at the world like 'God, why me?' - but it was something that I needed, I went through tremendous growth last year too."

Pettis added that once he overcame the initial disappointment and focused on recovery, he was able to turn the injury into a positive experience.

"Last year taught me how to really be happy. I feel refreshed, not just in my body, but in my soul as well," he said.

"I learned to sit back and figure out how to enjoy my life without competition and how to enjoy my life without making money. I had a year of just being happy for others.

"I spent a lot of time with my family, my friends, I didn't have a diet to worry about. I come from a Mexican family so everything is food, beer, drinking and kicking it, so I got to have some fun last year."

'Beating Patricio would be a dream come true'

While Pettis was side-lined, fellow American Patchy Mix won the bantamweight tournament, becoming the interim champion of the division.

Many fans and pundits expected Pettis' return fight to be against Mix to unify the division, but instead Bellator opted for Freire, who is stepping down to bantamweight for the first time in his 19-year career.

A double champion and veteran of 40 fights, with 27 of them being in Bellator, Pettis regards Freire as the greatest to ever compete in the promotion.

"It was a little left-field, everyone in the tournament was like 'why's this happening, we have an interim champion?' But I'm all in," said Pettis.

"This is a fight that gets me up in the morning. I'm nervous, I'm anxious, I'm scared. But I know I'm ready and this is what I live for, for this type of fight.

"It would mean a lot, to come back from a torn ACL, get the best Bellator fighter and come out successful. That would be a dream come true."

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