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Third Round is Dart's best doubles performance in a Grand Slam. She achieved this feat at the 2021 Wimbledon Championships alongside partner Johanna Konta. The pair defeated the 12th-seeded duo of Alexa Guarachi and Desirae Krawczyk in the first round, before overcoming Tereza Martincová and Markéta Vondroušová in the second round.