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Marin Čilić was defeated by Feliciano López in the 2017 Aegon Championship final. López, a Spanish professional tennis player, emerged victorious in a thrilling match, overcoming Čilić, a Croatian professional tennis player, in straight sets. López's triumph marked a significant achievement in his career, as he secured his first ATP 500 title and became the oldest player to win an ATP 500 tournament since 2010.