Mack distinguished himself again on the field of Neerwinden and had a leading part in the negotiations between Coburg and Dumouriez. He continued to serve as quartermaster-general, and was now made titular chief ("Inhaber") of a cuirassier regiment. He received a wound at Famars, but in 1794 was once more engaged in active service, having at last been made a major-general. But the failure of the coalition allies, due though it was to political and military factors and ideas, over which Mack had no control, was ascribed to him, as their successes of March–April 1793 had been, and he subsequently fell into disfavour in military circles. The Emperor, now Francis II, remained his supporter and in 1797 Mack was promoted Feldmarschall-leutnant, and in the following year he accepted, at the personal request of the emperor, the command of the Neapolitan army. He could do nothing with the unpromising material of his new command against the French revolutionary troops, and before long, being in actual danger of being murdered by his men, he took refuge in the French camp. Initially, he was promised a free pass to his own country, but Napoleon ordered that he should be sent to France as a prisoner of war.