Kell Brook has warned Gennady Golovkin that he feels stronger than ever ahead of their WBC and IBF middleweight title fight on Saturday.
Hundreds of people gathered in Covent Garden on Tuesday for the pre-fight sparring session ahead of the bout at the O2 Arena in London.
Both fighters go into Saturday's title fight with their unbeaten records on the line but Brook – who has jumped up two weight divisions to fight Golovkin – believes he will be a "monster" at this week's weigh-in.
"I feel strong; I feel like I've never felt before," Brook said.
"I've grown and put muscle on. I've been draining myself to make 147 for years. I feel more natural, more comfortable at this weight. I'm very hydrated. As soon as I started moving [on Wednesday] I started sweating, I've had many meals.
"I'm going to be a monster, and surprise everybody when they see me and Golovkin at the weigh-in."
Normally Brook would have to make 147lbs for the welterweight division but at middleweight the Sheffield-born boxer has been able to relax a bit more.
"It's terrible," he added. "Fight week — when you're that hungry you can't sleep, you struggle to even walk to the weigh-in.
"There's not even any fluid left in your eyeballs. You're that drained, that tight it's untrue. There's nothing in your mouth; there's nothing in you. It's a miracle how I do make it. I'm talking that tight.
"Yeah, [your mind is] playing tricks. You're always on and off the scales, going to the toilet, jumping back on the scales, having something to eat on the scales. Mentally, for weeks on end, it's, 'I'm not going to make this weight'.
"It drains you over a long period of time — 'I'm not going to make it this time, I'm in with someone who's going to be dangerous, I'm in a sport you can legally get killed in'. There's so much on your mind for weeks on end, and it takes something out of you.
"I'd just want to get into a dark room and hide away."