Angry Bagel Guy Drops Bagel Boss Nickname After Legal Threat

Chris Morgan hasn't even entered the ring yet for his celebrity boxing match against Lenny Dykstra and he's already taking a big L ... over his viral nickname.

The angry little guy from the bagel shop has dropped his Bagel Boss moniker for next month's bout at the Showboat Hotel in Atlantic City after the Bagel Boss chain of cafes flexed on him, legally speaking.

The stores, in NYC and all over Long Island, fired off a cease and desist letter to Chris.

As you can see ... he now goes by The Angry Bagel Guy. It's not as catchy, but it still gets the job done.

According to the letter -- obtained by TMZ -- the lawyer for Bagel Boss demanded Morgan and fight promoter Damon Feldman stop using its name for ads and promos for the event or risk getting sued for trademark violation.

We've learned that within hours of the legal threat being sent Monday, the changes were made and the Bagel Boss nickname was axed and replaced with the new one.

It's unclear if it'll be enough to ward off a lawsuit, though ... because the letter also demanded a public statement declaring Morgan has no affiliation with Bagel Boss. So far, we haven't seen it ... and there are still some old social media posts referring to him as Bagel Boss that have not been removed.

As we've told you ... Morgan signed on with Feldman to be part of his upcoming celeb boxing event after going viral earlier this summer for ranting against women on dating sites, challenging a couple of guys to fight and promptly getting his ass kicked.

He dug himself a further hole personality-wise during subsequent interviews -- including with us -- but managed to land the fighting gig. Former MLB star Lenny Dykstra was named Morgan's opponent last week and has already teed off on him ... with some micro-penis jokes.