The Condor Legion supported the Nationaists in the Battle of Bilbao and played a large role in defeating a Republican offensive in the Battle of Brunete, near Madrid. In attacking airfields, using the flak battalion on the front line, and committing the 20 Bf 109 fighters in the fighter escort role the Nationalists gained air superiority over the 400-strong Republican Air Force. The Nationalists destroyed 160 aircraft for the loss of 23. Sperrle's men routed eight battalions of infantry and large numbers of tanks in the close air support and interdiction role. From this point on, the Legion possessed general air superiority and the flexibility to transfer rapidly to other fronts to support the land war.