No shirt, pants OR undies were required at the Saints' postgame locker room celebration Sunday ... 'cause Mark Ingram got down with his bad self in nothing but a towel!!!
It all went down just minutes after New Orleans finished off the Eagles, 20-14, in a playoff win at the Superdome ... when the Saints turned their locker room into a nightclub.
The smoke was blowing ... the lights were flashing ... and that's when the Saints star RB took center stage to show off his best dance moves -- almost completely naked!!!
The rest of the New Orleans squad got in on the fun (with clothes on) .