Keys beats Kanepi to set up all-American semifinals at US Open

The US Open has truly lived up to its name in 2017.

Madison Keys defeated qualifier Kaia Kanepi 6-3, 6-3 in the quarterfinals on Wednesday, filling the fourth and final women's semifinals spot with a fourth American woman. It's the first time since 1981 there's been an all-American women's semis in New York.

Coming off two tough, tense, three-set matches in the third and fourth rounds, Keys put forth a remarkably calm, assured performance to advance with hardly a hint of stress against Kanepi.

Contributing to Keys' breezy 68-minute win was her cleanest, most brutally efficient serving display of the tournament. She mixed up her pattern beautifully, bombed eight aces, won 74 percent of her service points, and saved all three break points she faced. Any time there was even a whiff of danger, she served her way out of it.

Not that she got into much trouble, even when Kanepi managed to drag her into tit-for-tat baseline exchanges. Keys was steady and smothering, defending swiftly and changing the direction of the ball with aplomb. Kanepi is a power player who'd smacked 34 winners in her previous match, but she managed just eight on Wednesday.

It's the second career Grand Slam semifinals appearance for the 15th-seeded Keys, and her first since the Australian Open in 2015. She'll play CoCo Vandeweghe on Thursday for a spot in her first Slam final. In the other half, Venus Williams will take on Sloane Stephens.