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At the 2021 Cincinnati Open, Jil Teichmann reached the final after defeating Karolína Plíšková in the quarterfinals. Teichmann, who was ranked 37th in the world at the time, defeated the higher-ranked Plíšková in three sets, with a final score of 6-2, 6-4. Teichmann's strong performance and victory over Plíšková were significant achievements in her career and highlighted her potential on the WTA tour.