Conor Benn officially weighed in heavier than Chris Eubank Jr. on Friday, hitting the scales at 159.3 pounds while his rival came in at 159.1 pounds.
Ahead of their first fight in April, Eubank Jr. missed weight at 160.2 pounds on his first attempt, and 160.05 pounds on his second, missing the middleweight limit.
He was fined £375,000 ($500,000) at the time, per the conditions of contracts.
Benn weighed 156.4 pounds ahead of their first encounter, having come up from welterweight to make the fight.
Just as the first fight did, the rematch has a controversial 10 pound re-hydration clause, meaning neither fighter can weight over 170 pounds on the day of the fight.
When asked if he feels his body has adapted to the weight since the first fight, Benn said: "I do feel stronger for this fight, but in the back of my head I'll still want to get back down.
"It's not like I'm just cashing in and I've gone and see you lot later. I still want to do things in the game for myself that I want achieve."
Benn has insisted he will return to the welterweight division and attempt to win a world title at 147 pounds after Saturday's rematch.
He told reporters this week he believes he has no interest in a trilogy fight regardless of the result on Saturday. Benn said he will have two fights at welterweight before a move up to junior middleweight, which is fought with a 154-pound limit.
"We want to give the public the biggest fights possible and obviously it's financially rewarding for us, but you sit there and you go ... How much money do you need?" Benn said.
"I'm really excited to get back down to my natural weight and win a world title that cements my legacy for me, not for anybody else. Just for me.
"It's something I thought I couldn't do when I first turned over, I was so far away from achieving it to then achieving it.