Jason Derulo's Abs Lead Today's Star Sightings

Eat your heart out, Jordin Sparks.

Jason Derulo let everyone know exactly what his abs situation is like on Friday when he flashed his six-pack while onstage in Sao Paulo, Brazil. Lifting up his shirt to show his sculpted torso, the singer gave the crowd quite the eyeful during his performance.

Launch the gallery above for more of the day's star sightings!