By the 27th of August (after several days of increasing pressure against Australian patrols), Maj. Gen. Tomitaro Horii was ready to kick off the renewed Japanese offensive. By now his South Seas Detachment had grown to include all three battalions of 144th Infantry Regiment, and two more battalions of 41st Infantry Regiment were only days away. The Australians had only two complete infantry battalions in the area: the battle-tested 39th and the green 53rd. The first company from the veteran 2/14th Battalion had arrived the night before, but the remaining companies of 2/14th and all of 2/16th were still strung out along the Track. Unaware of the actual Japanese strength, the on-site commander Brigadier Potts decided to try and seize the initiative by sending 53rd Battalion up the eastern trail while using 39th and whatever parts of 2/14th arrived to hold the Japanese forces at Isurava. The 2/16th could take over the reserve role at Alola as they arrived during the next few days.

Thirty-Ninth Infantry Battalion had used the two-week lull to rebuild their ammunition stores and create firing lanes on the main approaches to Isurava village. It was enough to hold fast against the first probing attacks mounted by Maj. Gen. Horii. However, the green 53rd Battalion lost several of its officers in the first moments of contact and subsequently broke and scattered into the jungle. That gave Horii a perfect route to flank the Australians at Isurava, but he failed to take advantage of it.

Note the setup inadvertently shows the wrong orientation for the board. 34 should be in the top left hand corner.