Australian challenger Sakio Bika says he possesses the kryptonite to take down Canadian world champion Adonis "Superman" Stevenson.
Stevenson will defend his light heavyweight title against Bika in Quebec City next weekend.
It's a step up in weight class for former super middleweight champion Bika, but he has identified the confident Canadian's weakness.
"Every time he gets caught on the chin, he goes down," Bika said on Showtime.
Saturday's (Sunday AEDT) fight is receiving plenty of attention in America as it marks the return to live boxing on leading US free-to-air network CBS.
In the 1980s CBS was the home to world-title bouts, featuring marquee bouts with the likes of Sugar Ray Leonard and Ray "Boom Boom" Mancini.
