Top seed Ashleigh Barty inflicted defending champion Victoria Azarenka’s heaviest defeat in 14 years as she booked her place in the last eight of the Western and Southern Open in Cincinnati. Australia’s world No 1 Barty surged to a 6-0, 6-2 victory over Azarenka, wrapping things up in an hour and 11 minutes. There have been just two previous matches in the Belarusian’s career in which she has managed to win only two games, both coming in 2007 when she was aged 17. Barty will now play Barbora Krejcikova, who beat Garbine Muguruza 6-1, 6-7, 6-2. Second seed Naomi Osaka, beaten by Azarenka in last year’s final, was stunned by Swiss wildcard Jil Teichmann, who hit back from a set down to win 3-6, 6-3, 6-3. World No 76 Teichmann will now play for a place in the semi-finals against compatriot and 10th seed Belinda Bencic, who advanced after Karolina Muchova retired due to injury while trailing 7-5, 2-1. Fifth seed Karolina Pliskova beat America’s Jessica Pegula 6-4, 7-6 to set up a last-eight clash with Spain’s Paula Badosa, who won 6-2, 7-6 against Kazakhstan’s Elena Rybakina. Petra Kvitova, the 11th seed, will play Germany’s Anna Kerber in the other quarter-final. Czech Republic’s Kvitova cruised through after a 6-2, 6-1 win against Tunisia’s Ons Jabeur and three-time Grand Slam winner Kerber overcame Latvian Jelena Ostapenko 4-6, 6-2, 7-5.