 After a day of furious fighting, during which the bastion of Spain changed hands twice, Suleiman eventually called off the attack.He sentenced Mustafa Pasha, his brother-in-law, to death for his failure to take the city, but eventually spared his life after other senior officials had pleaded with him for mercy.Mustafa's replacement, Ahmed Pasha, was an experienced siege engineer, and the Turks now focused their efforts on undermining the ramparts and blowing them up with mines while maintaining their continuous artillery barrages.