On 17 September, heavy fighting was underway at Merisor. On 18 September, after heavy fighting, the large German force commanded by General von Staabs pushed the Romanian troops back and entered Petrozsény.:99 The inexperienced Romanian 11th Division commander, Brigadier General Ioan Muică, retreated to Bumbești, allowing Sunkel's troops to take the Szurdok (Surduc) Pass on the following day. On 19 September, Erich von Falkenhayn assumed command of the German 9th Army.:99-100 In his memoirs, Erich Ludendorff stated that, on 19 September, the German troops were successful in throwing back the Romanian units near Petrozsény over the mountain ridge. Romanian forces still remained in the region, however. On 19 September, the Romanian front extended from Petrozsény to Mount Tulisini (Tulișa).