Both ladies had obviously been worked on by their glam squads, and both looked ultra-glam at the America's Got Talent Season 8 Pre-Show Red Carpet Event.
But it was Mel B, in her sky-blue bodycon minidress with metallic-edged cutouts and matching stilettos, that seemed to steal the limelight.
Heidi, of course, still looked hot in an animal-print midi dress and black T-bar heels.
Who do you think won this fashion contest? Leave a comment below.