At the start of the War of the Fifth Coalition, d'Aspré led a brigade in Michael von Kienmayer's small II Reserve Armeekorps consisting of the "Puteani", "Brezeczinsky", "Scovaud", "Kirchenbetter", and "Scharlach" grenadier battalions, plus a battery of eight 6-pounder cannons. In the Battle of Abensberg on 20 April 1809, Archduke Louis of Austria tried unsuccessfully to defend the line of the Abens River. During the morning, Louis called up Kienmayer's corps from Ludmannsdorf to support Joseph Radetzky von Radetz's left flank brigade near Siegenburg. During the afternoon, d'Aspré's grenadiers supported Radetzky as he fell back toward Pfeffenhausen. At 11:00 PM that night, Bavarian pursuers aggressively crossed the Große Laber stream and attacked. Radetzky borrowed one of d'Aspré's grenadier battalions and held the Hornbach hill south of Pfeffenhausen until the early morning hours.