On 8 October, Marshals Joachim Murat and Jean Lannes encountered Franz Xavier Auffenberg's division at the Battle of Wertingen. The French crushed the outnumbered Austrians and drove the survivors west to Günzburg. The next day, Mack and Ferdinand drew up their troops facing east on the south bank of the Danube near Günzburg. Mack deployed d'Aspré and a light force that included Tyrolean Jägers to hold and scout the north bank. Unknown to Mack, Marshal Michel Ney sent one of his divisions to seize the Günzburg bridges from the north that morning.