Serena Williams beat Tsvetana Pironkova in a battle of the mothers in the US Open quarter-finals ©Getty Images

"Picture Gallery"

Medvedev faced his Russian compatriot Rublev in the last eight, triumphing in straight sets ©Getty Images
Medvedev faced his Russian compatriot Rublev in the last eight, triumphing in straight sets ©Getty Images
Naomi Osaka overcame American Shelby Rogers in straight sets to reach the last four ©Getty Images
Naomi Osaka overcame American Shelby Rogers in straight sets to reach the last four ©Getty Images
Spain's Pablo Carreno Busta reached the last four after an epic five set victory against Canada's Denis Shapovalov ©Getty Images
Spain's Pablo Carreno Busta reached the last four after an epic five set victory against Canada's Denis Shapovalov ©Getty Images
Serena Williams recovered from a set down against Tsvetana Pironkova to reach the last four ©Getty Images
Serena Williams recovered from a set down against Tsvetana Pironkova to reach the last four ©Getty Images
Last year's runner-up Medvedev twice required treatment from the trainer on route to reaching the last four by beating fellow Russian Andrey Rublev ©Getty Images
Last year's runner-up Medvedev twice required treatment from the trainer on route to reaching the last four by beating fellow Russian Andrey Rublev ©Getty Images
Naomi Osaka wore a mask bearing the name of George Floyd before and after her match with Shelby Rogers ©Getty Images
Naomi Osaka wore a mask bearing the name of George Floyd before and after her match with Shelby Rogers ©Getty Images
Williams waves to the virtual screen of fans following her quarter-final win ©Getty Images
Williams waves to the virtual screen of fans following her quarter-final win ©Getty Images