The 1st Raiders had one more battle to go on Guadalcanal. In early October intelligence indicated that the Japanese were building up their forces west of the Matanikau in preparation for another offensive against the perimeter. Division headquarters decided to strike first to secure the crossings over the river. In a plan reminiscent of the beginnings of the previous operation, two battalions of the 5th Marines would move down the coast road, seize the near bank of the Matanikau, and fix the attention of the Japanese forces on the far side. Three other battalions would cross the Matanikau at the single-log bridge and attack north toward the sea. Once they cleared the far side of the river, a force would garrison Kokumbona and prevent further enemy operations in the vicinity. In addition to strengthening the assault forces, this time division provided ample fire support. All units were to move into position on 7 October in preparation for launching that attack the next morning.
When the 5th Marines deployed forward on 7 October, they ran into a Japanese company dug in on the near side of the river just inland from the sandbar. Edson’s 2nd Battalion managed to secure most of its assigned frontage farther upriver, but his 3d Battalion was unable to break the enemy resistance centered on a well-fortified defensive position. He committed Company L to the battle and then radioed division for reinforcements so he could reconstitute a regimental reserve. Division assigned Company A, 1st Raiders to the task and the unit marched off down the coast road to bivouac next to Red Mike’s CP.
That night the Japanese on the near side of the river probed the lines of the 3d Battalion, 5th Marines, and mauled the company nearest the sandbar. Early in the morning of 8 October, Edson decided to commit the raiders of Company A to the task of reducing the Japanese pocket. He placed Major Lewis W. Walt in charge of the effort. (Walt had been Company As commander until Edson had brought him over as operations officer for the 5th Marines.) The raiders drove in a few enemy outposts but could make little headway against the interlocking fires of the concealed Japanese positions. Meanwhile, heavy rains during the night had continued into the day, and division delayed the move across the river for 24 hours. Vandegrift also decided to alter his original plan to a quick envelopment of the west bank and a return to the perimeter.
Based on these changed circumstances and his own observation at close range of Company A’s predicament, Edson halted the attack on the strongpoint. His 3d Battalion would continue to encircle most of the enemy position, while Company A went into the defense on their right flank. The latter’s position was shaped like a horseshoe, with the left linking up with the 3d Battalion and facing south toward the bunker complex, the center facing west toward the sandspit, and the right on the beach facing north toward the sea. To fill out the thin line, mortarmen and company headquarters personnel occupied the left flank positions. The raiders expected a Japanese assault across the river mouth to relieve the surrounded bridgehead, so the Marines strung barbed wire at the friendly end of the sandbar. The remainder of the raider battalion came up the coast road and went into reserve.
Just after dusk the Japanese in the strongpoint rushed from their positions in an effort to break through to their own lines. They quickly overran the surprised left flank of Company A and hit the center of the raider line from the rear. The enemy who survived the close-quarters fighting in both locations then ran headlong into the wire, where fire from the remaining Marines cut them down. The lieutenant commanding the raider company tried to recover from the confusion and establish a fresh line farther back along the coast road. In the morning there was some more fighting with a handful of Japanese who had sought refuge in Marine foxholes. Company C of the raiders moved up to occupy the abandoned enemy position and killed three more Japanese still holed-up there. They found an elaborate complex of trenches and bunkers connected by tunnels to an underground command post. The Marines counted 59 bodies stacked up against the wire or strewn about the perimeter. The battalion lost 12 dead and 22 wounded during this stint on the Matanikau.
The raiders suffered one additional casualty during the operation. When Red Mike had gone over to the 5th Marines, he had taken with him his longtime runner, Corporal Walter J. Burak. While carrying a message along the river on the afternoon of 9 October, Japanese machine-gun fire killed the former raider. He was the last member of the 1st Raiders to die in action on Guadalcanal. On 13 October a convoy embarked the raider battalion for transport to New Caledonia.
There were barely 200 effectives left in the unit -just a quarter of the battalion’s original strength.