Rajeev Ram of the United States and Joe Salisbury (front) of Britain compete during the men's doubles final against Mate Pavic and Nikola Mektic of Croatia at the 2021 National Bank Open in Toronto, Canada, on Aug. 15, 2021. (Photo by Zou Zheng/Xinhua)

Mate Pavic (R) and Nikola Mektic of Croatia compete during the men's doubles final against Rajeev Ram of the United States and Joe Salisbury of Britain at the 2021 National Bank Open in Toronto, Canada, on Aug. 15, 2021. (Photo by Zou Zheng/Xinhua)

Mate Pavic (L) and Nikola Mektic of Croatia pose for photos during the awarding ceremony after the men's doubles final against Rajeev Ram of the United States and Joe Salisbury of Britain at the 2021 National Bank Open in Toronto, Canada, on Aug. 15, 2021. (Photo by Zou Zheng/Xinhua)

Rajeev Ram of the United States and Joe Salisbury (R) of Britain pose for photos during the awarding ceremony after the men's doubles final against Mate Pavic and Nikola Mektic of Croatia at the 2021 National Bank Open in Toronto, Canada, on Aug. 15, 2021. (Photo by Zou Zheng/Xinhua)

Reilly Opelka (L) of the United States shakes hands with Daniil Medvedev of Russia after their men's singles final at the 2021 National Bank Open in Toronto, Canada, on Aug. 15, 2021. (Photo by Zou Zheng/Xinhua)

Reilly Opelka of the United States poses with the trophy during the awawrding ceremony after the men's singles final against Daniil Medvedev of Russia at the 2021 National Bank Open in Toronto, Canada, on Aug. 15, 2021. (Photo by Zou Zheng/Xinhua)

Daniil Medvedev of Russia poses for photos with the trophy after the men's singles final against Reilly Opelka of the United States at the 2021 National Bank Open in Toronto, Canada, on Aug. 15, 2021. (Photo by Zou Zheng/Xinhua)