Second-ranked Elena Rybakina has been inching toward the top spot for weeks and will get there if she reaches the semi-finals, but the Kazakh's prospects are clouded by injury concerns.
Americans Coco Gauff or Jessica Pegula could also pounce -- if either bag the title and Sabalenka and Rybakina both falter in Flushing Meadows.
Those closest in pursuit aren't the only players Sabalenka has to worry about as she tries to become the first woman si…