The Russians attacked the Swedes on July 11 and once again met them deployed in an overextended line — with gaps and no reserve — extending two kilometres crossed over the Kokkola highway, with their right flank protected by the Perho river.

[1] In total: 1,200 men and 4 guns[3] The Swedes resisted stubbornly, the artillery on both sides duelled near the highway while the infantry fought intensely out on the bog; some Swedish battalions counterattacked and pushed several Russian lines back, until their reserve gave them enough weight to repulse the Swedish attack.

Jankovitj then reinforced his right flank with two battalions from the reserve — to encircle the Swedish left and gain access to the highway from behind — while his other battalions increased their activity at the front; this forced Fieandt to withdraw one kilometre, where he once again made a brief stand at a forest edge to buy time for the collection of wounded, before he eventually ordered a retreat towards Tunkkarin Silta, five kilometres away.

[1] The Swedish casualty report mentioned 159 privates and seven officers killed or wounded, however, this number excludes missing (an additional killed and captured); it is therefore likely that the total casualties in dead and wounded reached a sixth of their fighting force, excluding the prisoners.

[6] The effects of the battle at Lapua led to a Russian withdrawal, and the return of the Swedish sixth brigade to the main army, while Feiandt could advance as far as Karstula (a few Swedish miles southeast of the two-way intersection at Lintulaks) and still effectively protect the highway leading to Kokkola;[7] Fieandt, who had been reinforced by the other half of the 2nd Tavastehus Battalion and 230 Landwehr, was once again defeated by Jegor Vlastov, at the Battle of Karstula, on 21 August.