During the Ottoman invasion, two Serbian armies were set up to defend the Despotate, with the 1st army being commanded by Nikola Skobaljić in Dubočica, near Leskovac, and the 2nd army being on the banks of Sitnica River in Kosovo.

An initial invading Ottoman force heading from Sofia cut off Skobaljić's army from Serbia's north. Despot Đurađ Branković suggested that Skobaljić either surrender, or hide from the Ottoman army until John Hunyadi was able to reinforce or liberate the trapped half of the Serbian army, which would render the Ottomans to pillage and raze the rich southern part of the despotate with no resistance. The young voivode disobeyed the despot, and the invading Ottoman army coming from Macedonia was met by Nikola Skobaljić near Banja. The Serbs scored a decisive victory against the Ottoman army, employing guerrilla tactics.