The Prussian army marches in two columns toward Kay, one on the road directly to Kay, and the other on the road to Mosau.

Barely have they emerged from the ravines surrounding the town when they fall into combat with some Russian skirmishers.

The Prussians repulse the initial group, but the arrival of reinforcement means the onset of generalized action.

The Russians subsequently fire on the Prussians from the heights surrounding Kay.

General Heinrich von Manteuffel takes six battalions and attacks on the artillery; initially they throw him back.

A contemporary participant maintains that Manteuffel succeeded in over-running the positions and took forty pieces of cannon, but there is no official evidence to support his statement.

There are three assaults at Kay in that afternoon, and each is thrown back.

General Manteuffel had been injured in the attack on the position.

Wedel orders a full cavalry assault through the woods and against the Russian right flank.

When the superior Russian force counters, Prussian momentum falters with the lack of a second column of timely reinforcement.

Repeated assaults on the Russians entrenched in the heights result in massive losses for the Prussians.

In the last of these assaults, Moritz Franz Kasimir von Wobersnow leads eight battalions and six squadrons from Züllichau against the Russian right wing.

At the same time his cavalry penetrates the enemy's infantry line, but the Russian cavalry, supported by gunfire, drives them and the infantry back into the low ground.

In the second assault, Manteufel is injured and in the final one, General Wobersnow is killed.

Wedel loses up to eighty three hundred of his troops, although Frederick sees fit to announce losses of only eight hundred, and placed Russian losses at over seven thousand.

Frederick also blames the troops, calling them cowardly "scoundrels" despite their repeated and suicidal assaults.

He eventually estimates Prussian losses at fourteen hundred and the Russian losses at fourteen thousand but he is fooling himself.