Prelude The U.S. Lunga perimeter around Henderson Field in late September 1942

The U.S. Lunga perimeter around Henderson Field in late September 1942 before the arrival of the U.S. 164th Infantry Regiment. The Lunga River runs through the center of the map. The Matanikau River is off the map to the left.
On 12 October, a company of Japanese engineers began to break a trail, called the "Maruyama Road", from the Matanikau towards the southern portion of the U.S. Lunga perimeter. The trail traversed some 15 mi (24 km) of the most difficult terrain on Guadalcanal, including numerous rivers and streams, deep, muddy ravines, steep ridges, and dense jungle. Between 16 and 18 October, the 2nd Division began their march along the Maruyama Road, led by Nasu's unit and followed in order by Kawaguchi and Maruyama. Each soldier had been ordered to carry one artillery shell plus his pack and rifle. [23]
Early on the morning of 20 October, Maruyama reached the Lunga River. Believing that his units were about 4 mi (6.4 km) south of the airfield, he ordered the left and right wing units to advance abreast of each other parallel to the Lunga north towards the American lines and set the time of the attack for 18:00 on 22 October. Maruyama, however, was mistaken. He and his troops were actually 8 mi (13 km) south of the airfield. By the evening of 21 October, it was clear to Maruyama that his units would not be in position to attack the next day, so he postponed the attack to 23 October and put his men on half rations to conserve their dwindling food supply. At nightfall on 22 October, much of the 2nd Division still remained strung out along the Maruyama Road, but Maruyama ruled out any postponement of the attack. [24]
During this time, Sumiyoshi prepared his command to attack the American forces from the west. On 18 October, he began shelling Henderson Field with 15 150 mm (5.9 in) howitzers . What remained of the
4th Infantry Regiment under Colonel
Nomasu Nakaguma began to gather openly near Point Cruz (on the coast just west of the Matanikau). On 19 October, Colonel Akinosuka Oka led the 1,200 troops of his 124th Infantry Regiment inland across the Matanikau and began moving up the east bank towards high ground east of the river. [25]
On 23 October, Maruyama's forces struggled through the jungle to reach the American lines. Kawaguchi, on his own initiative, began to shift his right wing unit to the east, believing that the American defenses were weaker in that area. Maruyama—through one of his staff officers—ordered Kawaguchi to keep to the original attack plan. When he refused, Kawaguchi was relieved of command and replaced by Colonel Toshinari Shōji , commander of the 230th Infantry Regiment. That evening, after learning that the left and right wing forces were still struggling to reach the American lines, Hyakutake postponed the attack to 19:00 on 24 October. The Americans remained completely unaware of the approach of Maruyama's forces. [26]
On this day, the Japanese 11th Air Fleet under Jinichi Kusaka based at Rabaul sent 16 Mitsubishi G4M 2 "Betty" bombers and 28 A6M2 Zero fighters to attack Henderson Field. In response, 24 F4F-4 Wildcats and four P-400 Airacobras from the CAF (Cactus Air Force) rose to meet them, resulting in a large aerial battle. To Allied observers, the Japanese appeared to lose several aircraft in the day's engagements, but their actual losses are unknown. The CAF lost one Wildcat to battle damage but the pilot was uninjured.