On 21 April, Napoleon attacked Johann von Hiller in the Battle of Landshut but the Austrians managed to avoid being trapped. However, Hiller's left wing lost an estimated 9,000 casualties during the day. Three of d'Aspré's grenadier battalions formed the Austrian rear guard as they retreated to Neumarkt-Sankt Veit. D'Aspre was present at the Battle of Neumarkt-Sankt Veit on 24 April, when Hiller lashed out at his Bavarian and French pursuers. Kienmayer's force retreated through Braunau am Inn on 26 April. D'Aspré missed the hard-fought Battle of Ebelsberg on 3 May. Hiller unwisely sent Kienmayer's troops to Asten, even as the French were in the process of driving in his rear guards. Nevertheless, d'Aspré's promotion to Feldmarschall-Leutnant came through the next day.