|Two-time Wimbledon champion Petra Kvitova beat current Wimbledon champ Garbine Muguruza|
Kvitova, whose progress has been slow but steady since a horrifying knife attack on her left hand in December, showed similar fighting spirit that won her the Birmingham title this year as she dismissed the third seed 7-6(3) 6-3 in one hour and 45 minutes.
The twice Wimbledon champion, playing in only her eighth tournament since her career-threatening injury, set up a last eight clash with Venus Williams after the American dumped out Spaniard Carla Suarez Navarro 6-3 3-6 6-1.
Venus has reached grand slam finals at the Australian Open and Wimbledon this year and Kvitova said she would have a tough task ahead.
“It will be a great match for me to step on Ashe again probably and play there. I mean, we always had tough battles. I will try my best. I mean, she has a big serve, big server of course,” she said.
Wildcard Sharapova, who played in her first major since a 15-month doping ban, said there were a lot of positives in her defeat by Sevastova. “Just competing, you know, being in that competitive environment. That’s what I missed,” she said.
Sharapova’s power play was nullified by the 16th seed’s control and delicate touch, and she eventually ground out a 5-7 6-4 6-2 win in two hours and 16 minutes.
Sevastova meets the unseeded Sloane Stephens after the American reached the quarter-finals for the first time in her career with a 6-3 3-6 6-1 win over Julia Goerges of Germany.
Sam Querrey, the last American standing in the men’s singles, powered past Germany’s Mischa Zverev 6-2 6-2 6-1 in one hour and 15 minutes, the shortest completed men’s singles match of the tournament so far.
Next up for Querrey, the first American man to reach the U.S. Open quarter-finals since 2011, is South Africa’s 28th seed Kevin Anderson, who outlasted Italian Paolo Lorenzi 6-4 6-4 6-7(4) 6-4.
Canadian teenager Denis Shapovalov was knocked out by Pablo Carreno Busta 7-6(2) 7-6(4) 7-6(3) and the Spaniard was joined in the last eight by Argentine Diego Schwartzman who downed 16th seed Lucas Pouille of France 7-6(3) 7-5 2-6 6-2.
Results from the U.S. Open Men’s Singles Round 4 matches on Sunday:
17-Sam Querrey (U.S.) beat 23-Mischa Zverev (Germany) 6-2 6-2 6-1
12-Pablo Carreno (Spain) beat Denis Shapovalov (Canada) 7-6(2) 7-6(4) 7-6(3)
28-Kevin Anderson (South Africa) beat Paolo Lorenzi (Italy) 6-4 6-3 6-7(4) 6-4
29-Diego Schwartzman (Argentina) beat 16-Lucas Pouille (France) 7-6(3) 7-5 2-6 6-2
Results from the U.S. Open Women’s Singles Round 4 matches on Sunday:
13-Petra Kvitova (Czech Republic) beat 3-Garbine Muguruza Blanco (Spain) 7-6(3) 6-3
16-Anastasija Sevastova (Latvia) beat Maria Sharapova (Russia) 5-7 6-4 6-2
Sloane Stephens (U.S.) beat 30-Julia Goerges (Germany) 6-3 3-6 6-1
9-Venus Williams (U.S.) beat Carla Suarez Navarro (Spain) 6-3 3-6 6-1