Albert's reputation as a military commander suffered badly when he was defeated by the Dutch stadtholder Maurice of Orange in the battle of Nieuwpoort on 2 July 1600. His inability to conclude the lengthy siege of Ostend (1601–1604), resulted in his withdrawal from the tactical command of the Spanish Army of Flanders. From then on military operations were led by the Genoese Ambrogio Spínola. Even though he could not prevent the almost simultaneous capture of Sluis, Spínola forced Ostend to surrender on 22 September 1604. He seized the initiative during the next campaigns, bringing the war north of the great rivers for the first time since 1594.