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What was Michiel de Ruyter's first goal in the First Anglo-Dutch War
During the First Anglo-Dutch War of 1652–1654, Michiel de Ruyter was asked to join the expanding Dutch fleet as a junior flag-officer or commandeur
What did being asked to join the expanding Dutch fleet lead Michiel de Ruyter to
Michiel de Ruyter proved his worth under the supreme commander lieutenant-admiral Maarten Tromp. The rank of admiral-general was reserved for the stadtholder, but no-one held that appointment.

Question: who did he defeat
Self-contained rewrite: who did Michiel de Ruyter defeat as Vice-Commodore in the First Anglo-Dutch War