RCT-31, later known as "Task Force Faith," was a hastily formed regimental combat team from the 7th Infantry Division that guarded the right flank of the Marine advance towards Mupyong-ni. Before the battle, RCT-31 was spread thin, with main elements separated on the hills north of Sinhung-ni, the Pyungnyuri Inlet west of Sinhung-ni, and the town of Hudong-ni () south of Sinhung-ni. Although the Chinese believed RCT-31 to be a reinforced regiment, the task force was actually understrength, with one battalion missing, due to the bulk of the 7th Infantry Division being scattered over northeast Korea.