The US troops were opposed by elements of the Japanese 17th Division (Lieutenant General Yasushi Sakai), which had previously served in China before arriving on New Britain in October and November 1943. These troops were known as "Matsuda Force", after their commander, Major General Iwao Matsuda and consisted of the 65th Brigade, with the 53rd and 141st Infantry Regiments and elements of the 4th Shipping Group. These troops were supported by field and anti-aircraft artillery, and a variety of supporting elements including engineers and signals troops. Just prior to the battle, there were 3,883 troops in the vicinity of Cape Gloucester. Matsuda's headquarters had been at Kalingi, along the coastal trail northwest of Mount Talawe, within of the Cape Gloucester airfields but after the Allied bombardment prior to the battle, it had been moved to Egaroppu, closer to Borgen Bay. The headquarters at Kalingi was taken over by the Colonel Koki Sumiya, commander of the 53rd Infantry Regiment, which defended the airfields primarily with the regiment's 1st Battalion, supported by elements of two artillery battalions, a heavy weapons company and a battalion of anti-aircraft guns. The 2nd Battalion, 53rd Infantry Regiment was in reserve around Nakarop, while the 141st Infantry Regiment (Colonel Kenshiro Katayama) was positioned well to the south around Cape Bushing. At the time of the fighting around Cape Gloucester, the effectiveness of these troops had been degraded by disease and lack of supplies, due to interdiction of the Japanese coastal supply barges. Air support was available from the naval 11th Air Fleet and 6th Air Division.