Jennifer Lopez came down to earth with a bump when her energetic dance routine went awry at the American Music Awards.

The 40-year-old star's famously ample derrière collided with the stage during her boxing-themed performance of new single Louboutins.

After climbing up onto the shoulders of her shirtless male dancers, the mother of two seemed to misjudge her dismount, landing on her rear rather than her feet.

But, ever the pro and possibly thankful for the little extra padding, J-Lo quickly wiped the grimace from her face and carried on with the routine.

American Music Awards 2009: Red Carpet Round Up