On dat ass

From I drink sport

On dat ass or On ya ass

 A term used in sports in order to show a mockery of someone.

Generally used when one individual does something to another individual that makes the person look amateurish.

Sports Use

This is a great term to use when watching basketball with the fans of another team. Highly effective when used with another Sports Term such as Ballgames.

Example

 Background: Syracuse vs Georgetown, at a Buffalo Wild wings with friends
 and fans of other teams within speaking distance.
 ---------------------------
 Bill would say loudly after an in the face dunk by Paul Harris on a 
 Georgetown player, "Oh Shit! Paul Harris just put it on ya ass GTOWN"
 (He also spit in a few Georgetown fans faces when he spoke, accidently)

The effectiveness of the use "on dat ass" or "on ya ass" is really well done in this situation. He correctly used the term after a mockery of the other team and in the presence of that teams fans. The accidental spit is an accepted form of silent "on ya ass" because the spitter put the spit "on ya ass". (note: real spitting on purpose is grounds for an ass kicking)