On 12 February 1919, the Germans took control of the forebridge area near Wielki Grójec which was a good location to start an attack on Wolsztyn from the vicinity of the Grójeckie Lake. Liquidation of the forebridge was therefore a necessary tactical move.

Few details are known about the course of the fighting. The 2nd Poznań Battalion was to start the attack. The forebridge was attacked by two separate groups. Victory was within reach, when suddenly a German unit, marching from Wielki Grójec to replace the German soldiers who were stationed there, appeared unexpectedly. The sudden attack and the doubling of enemy forces determined the victory of Germans. One of the Polish groups was pushed back while the other one (North) was surrounded and destroyed; its Commander, known for his participation in battles that took place in December in Poznań, Second Lieutenant Edmund Krause, committed suicide, also Second Lieutenant Maksymilian Moellenbrok was killed. In total, 32 insurgents were killed and 35 were wounded. 40 German soldiers were killed and 70 were wounded. Although Wielki Grójec was successfully defended, the insurgents failed to push the Germans out of the forebridge area.

The tragic result of this otherwise well planned action was a result of poor reconnaissance of the German forces by the Poles. The fact of the attack of the second German unit on the already fighting insurgents proves the exceptional imprudence of the Polish command that did not manage to obtain up-to-date information about the enemy on time, who, in this instance were already coming. The defeat, which was a consequence of negligent reconnaissance, was not offset by the heroic attitude of the soldiers and the admirable perseverance of both fallen commanders.