In the three-day battle the Ottoman army under the command of Sultan Murad II defeated the Crusader army of regent John Hunyadi. Calculating that he would need more than 40,000 men to defeat the Ottomans, the Hungarian regent sought to join up with anti-Ottoman Albanian forces, possibly led by Skanderbeg. The Ottomans in their base at Sofia received word of the Crusader army's march route and subsequently began readying their men.