Meanwhile, the two main armies fought at the Battle of Borodino on 7 September 1812. At Borodino, Grouchy's corps included the divisions of Chastel and Houssaye. In the final successful French attack on the Great Redoubt, Grouchy's III Cavalry Corps was to the left, Prince Eugène de Beauharnais' IV Corps was in the center, and the II and IV Cavalry Corps were on the right. While the right flank cavalry and infantry overran the fortification, Grouchy's cavalry galloped into the area behind the Great Redoubt only to find that there was a second line of Russian infantry deployed in squares to the east. A Russian cavalry countercharge was blunted but the French were unable to advance beyond the captured redoubt. Houssaye was badly wounded at Borodino and became a Russian prisoner when the hospitals at Vilnius were abandoned on 10 December. Units of the corps were engaged at the Battle of Tarutino on 18 October. These were the French 6th "Chasseurs-à-Cheval", 6th Hussar, and 23rd Dragoon Regiment and the Württemberger 3rd "Jäger zu Pferde" Regiment. By this time, battle losses and illness had shrunk Grouchy's corps to only 700 mounted men.