Sabalenka's Reign Faces New Test at US Open The US Open has long been a proving ground for tennis' biggest stars. This year, however, it seems more like a referendum on dominance.
Aryna Sabalenka's grip on the world rankings is about to face its stiffest challenge yet in Jessica Pegula.
Pegula's narrow victory over Emma Navarro sets up a thrilling semifinal showdown with two time defending champion Sabalenka.