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Barbora Krejčíková has won all her women's doubles majors with Kateřina Siniaková. The two Czech players won the French Open in 2018 and 2021, Wimbledon in 2018, and the US Open in 2018. They also reached the final of the Australian Open in 2019. Krejčíková and Siniaková are considered one of the best women's doubles teams in the world.