An observer from the 1st Battalion, 7th Marines, spotted an enemy officer surveying Edson's Ridge on the 24th, and scout-snipers reported smoke from numerous rice fires rising from a valley about two miles south of Lieutenant Colonel Puller's positions. Six battalions of the Sendai Division were poised to attack, and near midnight the first elements of the enemy hit and bypassed a platoon-sized outpost forward of Puller's barbed-wire entanglements. Warned by the outpost, Puller's men waited, straining to see through a dark night and a driving rain. Suddenly, the Japanese charged out of the jungle, attacking in Puller's area near the ridge and the flat ground to the east. The Marine replied with everything they had, calling in artillery, firing mortars, relying heavily on crossing fields of machine gun fire to cut down the enemy infantrymen. Thankfully, the enemy's artillery, mortars, and other supporting arms were scattered back along the Maruyama Trail; they had proved too much of a burden for the infantrymen to carry forward.
A wedge was driven into the Marine lines, but eventually straightened out with repeated counterattacks. Puller soon realized his battalion was being hit by a strong Japanese force capable of repeated attacks. He called for reinforcements and the Army's 3d Battalion, 164th Infantry (Lieutenant Colonel Robert K. Hall), was ordered forward, its men sliding and slipping in the rain as they trudged a mile south along Edson's Ridge. Puller met Hall at the head of his column, and the two officers walked down the length of the Marine lines, peeling off an Army squad at a time to feed into the lines. When the Japanese attacked again as they did all night long, the soldiers and Marines fought back together. By 0330, the Army battalion was completely integrated into the 1st Battalion, 7th Marines' lines and the enemy attacks were getting weaker and weaker. The American return fire--including flanking fire from machine guns and Weapons Company, 7th Marines' 37mm guns remaining in the positions held by 2d Battalion, 164th Infantry, on Puller's left--was just too much to take. Near dawn, Maruyama pulled his men back to regroup and prepare to attack again
With daylight, Puller and Hall reordered the lines, putting the 3d Battalion, 164th, into its own positions on Puller's left, tying in with the rest of the Army regiment. The driving rains had turned Fighter One into a quagmire, effectively grounding Cactus flyers. Japanese planes used the "free ride" to bomb Marine positions. Their artillery fired incessantly and a pair of Japanese destroyers added their gunfire to the bombardment until they got too close to the shore and the 3d Defense Battalion's 5-inch guns drove them off. As the sun bore down, the runways dried and afternoon enemy attacks were met by Cactus fighters, who downed 22 Japanese planes with a loss of three of their own.
As night came on again, Maruyama tried more of the same, with the same result. The Army-Marine lines held and the Japanese were cut down in droves by rifle, machine gun, mortar, 37mm, and artillery fire. To the west, an enemy battalion mounted three determined attacks against the positions held by Lieutenant Colonel Herman H. Hanneken's 2d Battalion, 7th Marines, thinly tied in with Puller's battalion on the left and the 3d Battalion, 7th Marines, on the right. The enemy finally penetrated the positions held by Company F, but a counterattack led by Major Odell M. Conoley, the battalion's executive officer, drove off the Japanese. Again at daylight the American positions were secure and the enemy had retreated. They would not come back; the grand Japanese offensive of the Sendai Division was over.