Kostyuk earns best win by ranking against Gauff in Stuttgart quarters
The Ukrainian came from a set down to beat the US Open champion in a rematch of their Australian Open quarterfinal, which Gauff won in a similarly-epic three sets.
13 Tournaments in Play
See Live ScoresThe top seed improved to 10-0 to reach the Porsche Tennis Grand Prix semis.
The Tennis.com app has everything you need to follow your favorite sport.
The Romanian is happy to provide an accountable explanation, while ready to move forward.
For on-court news and off-court happenings, stay in the know through your inbox.