Third Armoured Brigade and C Brigade of the Beauman Division, a hastily-organized collection of reservists from the Pioneer Corps, held a thin line along the marshy Andelle River. On the evening of 7 June, R Battalion found a French cavalry regiment south of Forges-les-eaux but it withdrew early in the morning; the arrival of some tanks compensated for this defection. The next morning began as a fine and quiet day.

At 1000, as German motorcyclists neared the main bridge it exploded. Later German tanks attacked the left flank covering the level crossing but they pulled back when the British cruiser tanks opened fire. The British claim that not long afterwards two columns of French tanks approached the right flank where their arrival had been expected. As soon as they were through, they traversed their guns and opened fire on the defenders from the rear, while the main German forces pressed in from the front over a wide area. After action reports stated that the tanks were French, but it seems that these were German tanks having found a ford in the river some 400 meters downstream. By afternoon the line of the Andelle was fatally ruptured and 7th Panzer Division poured through the gap. The outflanked R Battalion fell back to Rouen.