Gael Monfils of France in action against John Isner of the USA during their quarterfinals match at the National Bank Open tennis tournament in Toronto, Canada, 13 August 2021. EPA-EFE/WARREN TODACamila Giorgi of Italy in action against Cori Gauff of the USA during their quarterfinal match at the National Bank Open tennis tournament in Montreal, Canada, 13 August 2021. EPA-EFE/Andre PichetteDaniil Medvedev of Russia in action against John Isner of the USA during their semifinal match of the National Bank Open tennis tournament in Toronto, Canada, 14 August 2021. EPA-EFE/WARREN TODAAryna Sabalenka of Belarus reacts after she missed a point against Karolina Pliskova of Czech Republic during the semifinals of the Rogers Cup Women’s tennis tournament in Montreal, Canada, 14 August 2021. EPA-EFE/ANDRE PICHETTEReilly Opelka of the US celebrates his win over Stefanos Tsitsipas of Greece in the semifinals of the National Bank Open men’s tennis tournament in Toronto, Canada, 14 August 2021. EPA-EFE/WARREN TODAKarolina Pliskova of Czech Republic in action against Sara Sorribes Tormo of Spain during the quarterfinal of the Rogers Cup Women’s tennis tournament in Montreal, Canada, 13 August 2021. EPA-EFE/ANDRE PICHETTEStefanos Tsitsipas of Greece in action against Reilly Opelka of the US during the semifinals of the National Bank Open men’s tennis tournament in Toronto, Canada, 14 August 2021. EPA-EFE/WARREN TODAOns Jabeur of Tunisia gestures after winning the first set against Jessica Pegula of the USA during their quarterfinal match at the National Bank Open tennis tournament in Montreal, Canada, 13 August 2021. EPA-EFE/Andre PichetteSara Sorribes Tormo of Spain reacts after she lost a set against Karolina Pliskova of Czech Republic during the quarterfinal of the Rogers Cup Women’s tennis tournament in Montreal, Canada, 13 August 2021. EPA-EFE/ANDRE PICHETTE