It is sometimes claimed that the poor coordination between Samsonov and Rennenkampf during the campaign was based on their personal antagonism towards each other. This antagonism is said to have been based on an incident after the Battle of Liaoyang during the Russo-Japanese war where Samsonov had publicly quarrelled with Rennenkampf on the landing platform of a railway station, and that the two were mutual lifetime enemies. However, the original source of this story is considered to be Max Hoffmann, at that time a colonel on the staff of the German Eighth Army. His claim of first hand knowledge of the disagreement is contradicted by the injuries to Rennenkampff at the time. Hoffman appears to have advanced this story during planning sessions, in support of his argument that Rennenkampf would not come to the aid of Samsonov. He argued that the German Eighth Army was free to use all of its forces in the attack on the Russian Second Army to their south, without fear of a counter-attack from their rear by the Russian First Army.