J'Den Cox reacts after beating Kyle Dake in their 86-kilogram freestyle final match at the U.S. Olympic Wrestling Team Trials, Sunday, April 10, 2016, in Iowa City, Iowa. (AP Photo/Charlie Neibergall)

U.S wrestler J'Den Cox will try to prove he's one of the toughest men in the world this summer at the Rio Olympics.

But he's got a soft spot for singer Justin Bieber _ and perhaps a future in Bieber's profession once he retires.

Cox, who will wrestle for the Americans in men's freestyle at 86 kilograms, recently broke into an impromptu version of Bieber's "Love Yourself" during a break in training for this weekend's World Cup in Los Angeles.

Cox is considered one of the brightest young stars in U.S. wrestling, largely because of his tenacity and ferociousness on the mat.

But there's nothing ferocious about Cox's signing voice, as you can see below.