During this period, Despot Stefan was collecting his forces, and military support he received from Sigismund, but also of his son in law Sandalj Hranić Kosača. His forces were met with Mehmed I commanders near Kruševac and after the agreement there was a merger of their armies, which were sent to the south. At the mouth of the Toplica river at Dobrič, near Koprijan, they were joined by some Musa supporters, including the commander of the army Evrenos, after which they continued traveling to Ovče Polje. Stefan, Sandalj Hranić Kosača and Jovan Morović at Skopska Crna Gora leave troops and return to Serbia, and command of them took Đurađ Branković.