In the pass, the Greeks were ambushed by the Bulgarian 2nd and 4th Armies which was newly arrived from the Serbian front and had taken up defensive positions there. However, after bitter fighting the Greek side managed to break through the Kresna pass. The Greek advance continued and on July 25, the village of Krupnik, north of the pass, was captured, forcing the Bulgarian troops to withdraw to Simitli. Simitli was also captured on July 26, while at the night of July 27–28 the Bulgarian forces were pushed north to Gorna Dzhumaya (Blagoevgrad), 76 km south of Sofia.