Video: Kuznetsova and Kvitova advance to quarters while Williams reaches semis

Seventh seed Petra Kvitova of the Czech Republic and unseeded Russian Svetlana Kuznetsova advanced to the quarter-finals of the Toray Pan Pacific Open in straight sets on Thursday – before Venus Williams also kept up her winning streak going, and gained a berth in the semi-finals, with a 6-3, 6-7 (4-7), 6-3 win over Canada’s Eugenie Bouchard.

Seventh seed Petra Kvitova eased into the quarter-finals of the Toray Pan Pacific Open on Thursday with a straight sets 6-2, 6-2 win over 18-year-old American Madison Keys.

The 23-year-old took an hour and 15 minutes to wrap up the match and will now face Russian Svetlana Kuznetsova in the last eight.

Kuznetsova, a former US Open and French Open champion, was taken to a tie-break in the first set of her third round contest against Romanian Sorana Cirstea but won it 7-3.

Cirstea folded after that and 28-year-old Kuznetsova, ranked 27th in the world, won the second set 6-1 to advance in straight sets.

Venus Williams beat Canadian teenager Eugenie Bouchard 6-3, 6-7 (4-7), 6-3 to advance to the semi-finals for the first time.

The unseeded former world number one and seven-time Grand Slam champion, whose previous best in Tokyo was the quarter-finals in 2004, broke Bouchard with a forehand down the line to go up 5-2 in the third set – and then held on to win a match that lasted three hours.

Williams will now face either Svetlana Kuznetsova or Petra Kvitova in the semis.