It is on between mentor and protege.
According to the latest issue of Men's Health, Usher has "the best abs in the entertainment industry," a ranking that may very not sit very well with fans of the singer he discovered.
Seriously, have you see this video of Justin Bieber shirtless?!?
Usher will star in an upcoming film as Sugar Ray Leonard and says he's been training "like an athlete everyday" in preparation - and the guy does look good.
But better than Bieber with his shirt off?!? We'll leave this to the readers. Compare, contrast, drool and vote now:
It's an ab-off! Compare Usher with Justin Bieber now and decide who has the best abdominal muscles. View Poll »