Tennis: Calm Stephens edges Osaka, Kerber stunned by Bertens

A calm Sloane Stephens picked her shots to perfection to overcome Japan's Naomi Osaka in a battle between the last two U.S. Open champions at the WTA Finals on Monday before top seed Angelique Kerber was upset by Kiki Bertens.

from Reuters: Sports News https://reut.rs/2yZxfv4