Carl Frampton has revealed how his body ached for days after his first fight with Kiko Martinez nine years ago.
Frampton beat Martinez twice in Belfast to win the European and then the World super-bantamweight titles.
The first win came via a knockout in the ninth round at the SSE Arena in 2013.
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The World title success was secured with a comprehensive points victory at the Titanic Slipway one year later.
While both wins were impressive performances from Frampton, the Jackal admits his body was left in bits after duelling with current IBF World featherweight champion Martinez, who defends his title this weekend against Josh Warrington.
Frampton told Radio 5 Live's Boxing with Steve Bunce show: "You just have to look at my face after the (second) fight.
"And although it was one-sided on the judges' scorecards it was a tough fight and I had to be really switched on throughout the fight.
"But going back to the first fight, I think people forget how hard that was. They remember the stoppage and that it was a KO win for me, but it was nip and tuck and I struggled for a week or so after that fight.
"My hands were sore, my body was sore. It was a brutal, brutal fight for me.
"I struggled bad for about a week or 10 days after that fight. I was sore. But it was worth it."
Martinez sensationally won the IBF World featherweight belt with a knockout win over Kid Galahad back in November.
The 36-year-old has now fought 55 times as a professional, and despite losing 10 times 'La Sensacion' has returned to the top step of the sport.
Ahead of his rematch with Warrington, who beat Martinez five years ago, Frampton said: "I am delighted Kiko is getting another big opportunity now.
"He is world champion and getting another good pay day, which he fully deserves.
"He is an absolute throwback."
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