From January 1798 to March 1799, Zach was chief of staff of the "Armee von Italien". He assumed the chief of staff role again from July 1799 to June 1800. On 9 June 1799 he received promotion to General-major. In a private letter to the Russian ambassador that was opened by the Austrian government, the army commander Alexander Suvorov described Zach as "sound, discreet and professional, but a great deviser of "Unterkunft" (logistics) just when I want to burst into flaming action." Though Suvorov used "Unterkunft" as a pejorative, Zach was tickled rather than insulted when shown the letter. Zach performed capably at the Battle of Novi on 15 August. For his actions, a grateful emperor awarded him the Knight's Cross of the Military Order of Maria Theresa on 13 October 1799. A skilled mathematician, Zach was more at home in the field of military engineering than he was at combat leadership or in an operational role.