On the east coast, the 22nd Brigade fought a series of delaying actions around Mersing, as the Japanese advanced. On 26 January, the 2/18th Battalion launched an ambush around the Nithsdale and Joo Lye rubber plantations, which resulted in heavy Japanese casualties and briefly held up their advance allowing the 22nd Brigade time to withdraw south. Meanwhile, the remainder of the 27th Brigade waged a rearguard action around the Ayer Hitam trunk road, while the 22nd Brigade was sent back to guard the north end of the Johore–Singapore Causeway which linked the Malayan Peninisula to Singapore, as Allied forces retreated.