Marty served as the deck officer on the New Republic Defense Force Fifth Fleet's flagship, the Intrepid. He was a staff officer working for General Etahn A'baht throughout the fleet's assignment to the Farlax sector during the Black Fleet Crisis.
When Han Solo arrived on the ship before the Fifth Fleet left Coruscant, Marty was there to welcome him. Similarly, when General A'Baht came back, Marty informed him that General Solo was on board.