The gloves were set to hit the auction block next month during an event organized by Profiles In History -- a pretty well-known memorabilia dealer.
But once Stallone got wind of the event -- his lawyer, legal pit bull Marty Singer, fired off a cease and desist letter to PIH stating, "Be advised that these items are not 'Sylvester Stallone's boxing gloves from the first Rocky' and they are not authentic."
Stallone threatened to sue if the items weren't 86'd from the auction ASAP.
PIH obliged -- and says it is "withdrawing the items pending further research." Though a rep tells us the company is VERY confident the gloves are legit.