The 'Battle of Sarimbun Beach' was the first stage of the Japanese assault on the north-western corner of Singapore island, in the sector held by Australian and allied forces (8/9 February 1942).

This was the area in which Japanese troops of Lieutenant General Tomoyuki Yamashita’s 25^th Army first attacked the British-led allied forces in Singapore toward the end of the 'E' (i) Japanese conquest of Malaya and Singapore. The commander of all Allied forces in Singapore, Lieutenant General A. E. Percival, had not expected the Japanese to make their main attack on the island from the north-west, but rather the north-east, and had thus not reinforced Brigadier H. B. Taylor’s Australian 22^nd Brigade, which therefore took the brunt of the Japanese assault. The immediate Japanese objective after the landing at Sarimbun Beach was the capture of Tengah airfield.

Percival gave the two brigades of Major General H. G. Bennett’s Australian 8^th Division responsibility for the north-western sector of the island. Here the terrain was primarily mangrove swamp and tropical forest, broken by rivers and creeks. Taylor’s Australian 22^nd Brigade and most of the Australian 2/4^th Australian Machine Gun Battalion, were assigned a sector 10 miles (16 km) wide along Sarimbun Beach with the Jind Battalion of the Indian States Forces that was guarding Tengah, and one company of 'Dal' Force, a guerrilla militia recruited from Singaporean Chinese. The Australian 27^th Brigade was assigned an adjoining 4,000-yard (3660-m) wide area to the north, adjoining the now-blown causeway linking Johore and Singapore island across the Straits of Johore. The Australian 2/4^th Machine Gun Battalion was distributed among the infantry units.

At 20.30 on 8 February, Australian machine-gunners opened fire on vessels and craft carrying the first wave of 4,000 Japanese troops from Lieutenant General Takuro Matsui’s 5^th Division and Lieutenant General Renya Mutaguchi’s 18^th Division toward Singapore island. The Japanese wasted no time in assaulting Sarimbun Beach. Fierce fighting raged throughout the night in the area, but the increasing Japanese numerical strength, as well as their superiority in artillery, tanks, aircraft and military intelligence, eventually began to take their toll on the defenders. The Japanese managed to exploit several gaps, the inevitable result of the presence of small rivers, streams and creeks, in the thinly-spread allied defence line along the coast. By 00.00, the two Australian brigades involved in the defence of the beach had lost communication with each other and the Australian 22^nd Brigade was forced to retreat in confusion. At 01.00 on 9 February, yet more Japanese troops landed and the last Australian reserves were committed to the battle.

Toward dawn on 9 February, some elements of the Australian 22^nd Brigade had been overrun or surrounded, and in the centre the Australian 2/18^th Battalion had lost more than half of its men. The Australian 2/20^th Battalion, holding the right flank, was also heavily committed in resisting the Japanese troops. The Australian 2/19^th Battalion, on the left flank, was being outflanked, and only its 'B' Company was left to face the initial landings and assaults by the Japanese. Percival did not reinforce the depleted Australian 22^nd Brigade until Tengah airfield was threatened with capture. Before British and Indian infantry reinforcements arrived, the badly-battered Australian and Singaporean defence units, along with the Jinds, retreated to the Jurong Line stretching to the south from the village of Bulim in the area to the east of the airfield. Tengah airfield was taken by the Japanese at about 12.00 on 9 February.

Shortly after the fall of night on 9 February, three British Fairmile B motor launches were sent on a raid up the western channel of the Straits of Johore at the area of the coast adjoining Sarimbun Beach. Their primary objective was to attack Japanese landing-craft and disrupt Japanese communications. The launches came under fire from Japanese forces from Malaya in the north and Sarimbun Beach in the south, but pressed on almost as far as the causeway. A few Japanese landing craft were sunk before the launches withdrew to Singapore suffering minimal to almost no damage. Some Allied soldiers saw this as an example of effective defensive tactics that were used too little and too late by their senior commanders.