Wimbledon champion Garbine Muguruza swept into the semi-finals of the WTA hardcourt tournament at Stanford on Friday with a 6-1, 6-3 win over Ana Konjuh.

Spanish top seed Muguruza needed just 62 minutes to get past the fifth-seeded Croatian, breaking Konjuh's serve five times and never trailing in their first career meeting.

"I think today I was very accurate," said Muguruza, the world No 4 who is playing her first tournament since beating American Venus Williams in the final at Wimbledon to claim a second career Grand Slam title to go with her 2016 French Open crown.

"Ana is such a powerful player and super-young," Muguruza said.

"I knew I had to be concentrated. I'm super happy that I'm through to the semi-finals, and I'm pretty happy with the match."

Muguruza next faces either third-seeded American Madison Keys or seventh-seeded Lesia Tsurenko of Ukraine.

Second-seeded Czech Petra Kvitova's quarter-final clash with eighth-seeded American CiCi Bellis highlighted the night session, with the winner to take on either sixth-seeded American CoCo Vandeweghe or fourth-seeded Russian Anastasia Pavlyuchenkova.

The last time the top eight seeds reached the quarter-finals of a WTA tournament was in Philadelphia in 2004.

Source: AFP