"Monssen" returned to Guadalcanal 18 September to insure the integrity of an Allied supply line and to block Japanese efforts at resupply. On 8 November, she departed Nouméa with two cruisers and two other destroyers as Task Group 67.4 (TG 67.4), under Rear Admiral Daniel J. Callaghan, as escort for transports carrying reinforcements to the Marines on Guadalcanal. At the same time, another convoy set out from Espiritu Santo, covered by one cruiser and four destroyers under Rear Admiral Norman Scott. Arriving off Lunga Point on 12 November, a day after those from Espiritu Santo they commenced unloading. By dusk as reports of Japanese ship movements from Truk increased, 90 percent of the transports had been unladen despite afternoon torpedo plane attacks, one of which had cost "Monssen" the use of her fire control radar. The transports were pulled out, escorted through Lengo Channel, and seen safely on their way to Espiritu Santo. Then Admiral Callaghan's force, heavily outnumbered even with the addition of Admiral Scott's ships, reversed course and steamed back to engage the enemy in the initial action of what would later be called the Naval Battle of Guadalcanal.