 In order to try to keep to the "MO" timetable, Takagi was forced to abandon the delivery mission after the second attempt and direct his force towards the Solomon Islands to refuel.To give advance warning of the approach of any Allied naval forces, the Japanese sent submarines , , and to form a scouting line in the ocean about southwest of Guadalcanal.Fletcher's forces had entered the Coral Sea area before the submarines took station, and the Japanese were therefore unaware of their presence.