Two days after the landing a group of seven heavy cruisers, one light cruiser and four destroyers were sighted arriving in Rabaul from Truk, there to refuel and then sortie for a night battle against the supply ships in Empress Augusta Bay.
Two days after the landing the Japanese reinforced their forces at Rabaul by sending down a group of seven heavy cruisers they had been conserving at Truk, along with one light cruiser and four destroyers. At Rabaul the force refueled in preparation for a night battle against the supply ships in Empress Augusta Bay.