Good news for the Marine who scored a date with Ronda Rousey -- U.S.M.C brass is totally cool with the UFC champ turning up at the party.
We spoke to the Corps about Ronda showing up on Lance Corporal Jarrod Haschert's arm for the December ball, 'cause let's face it ... they don't get MMA superstars at these things ever year.
Capt. Kendra Motz told TMZ Sports, "We welcome her to enjoy our ceremonies."
We broke the story ... Haschert made a viral video inviting Rousey, then we saw her out in L.A. and she accepted! Getting the Marines to sign off was the last hurdle.
Captain Motz added, "It's exciting for all of our guests. It's a time to educate them on our traditions."
In other words, bring your dancing shoes, Ronda -- the date is on!!