The pair of 17-year-olds took the big prizes at Kalamazoo and San Diego.
The Canadian hopes to recover in time for the US Open, but isn't sure of her timeline.
Paul and Pegula are the first pair of Americans to take down the WTA and ATP World No.1 in the same week since Roddick and Serena in 2008.
A pre-match ritual has helped Alex de Minaur break through to his maiden Masters 1000 final.
The semis are set in Montreal after a long day of tennis.
Daniil Medvedev believes the tours need to find a way to standardize tennis balls at each event.
The Spaniard was blown away by the force of Ben Shelton's game in Canada
