CM Punk has long been a controversial figure in pro wrestling, but since his signing with the UFC a year ago, he’s quickly become one of the most polarizing figures in mixed martial arts as well.

Former Bellator Champion, undefeated Ben Askren has served as CM Punk’s wrestling coach since the wrestling superstar showed up at Roufusport in Milwaukee earlier this year. Askren, who deals with plenty of criticism of his own, thinks fans have a reason for disliking Punk.

“Maybe jealousy,” Askren told MMA Fighting this week. “I would guess that’s a pretty good answer. He’s been famous, he’s made a lot of money, he’s got a hot wife. There’s a lot of things about him that people would probably be jealous of. I would guess that’s it.”

See Also: CM Punk’s UFC Debut Postponed Due To Injury

Many fans also have speculated that the former WWE Champion Punk’s signing was simply a publicity stunt for both sides, and that he’d never actually fight. Askren says that if that’s the case, it would be a surprise to him.

“If he’s not gonna fight, he fooled me. I’ve heard that and people have asked me that. He’s in the gym all the time and he’s training all the time, so that would sure be a lot of effort to put into a publicity stunt. You’d think if it was a publicity stunt he’d maybe show up once a week or once a month. For a while before he was injured, he was in there twice a day, every day,” Askren said.

Askren will defend his ONE Fighting Championship in a rematch against Luis Santos on November 13. CM Punk’s UFC debut has yet to be booked.