Matthew Morrison to Acting Coach: I Don't Owe You Jack!!!

Matthew Morrison's refusing to pay his acting coach $182k ... claiming in a new lawsuit he never struck a ludicrous deal with the guy.

The former "Glee" star denies ever verbally agreeing to pay Peter Mattaliano 2.5% of his acting salary from any TV or movie roles. Matthew says Peter is demanding "this outrageous figure based upon a purported oral agreement" in May 2011.

Matthew denies ever agreeing to that deal, and says he actually did pay Peter generously in excess of what acting coaches are normally paid ... although he doesn't say a specific amount.