Alex De Minaur produced the upset of the day at the Brisbane International when the Australian teenager defeated 2016 champion Milos Raonic in straight sets to reach the quarter-finals on Wednesday. The 18-year-old wildcard, ranked No 208 in the world, broke Raonic’s fearsome serve three times en route to a 6-4, 6-4 victory, much to the delight of the home support. De Minaur will next face another victor from an earlier upset in Michael Mmoh. The American teenager, ranked No 175, defeated Germany’s world No 33 Mischa Zverev 6-2, 5-7, 6-4 to take his place in the last-eight. <strong>____________________________________________________</strong> <strong>Read more:</strong> <strong>____________________________________________________</strong> Raonic withdrew from last week’s Mubadala World Tennis Championship in Abu Dhabi to continue his recovery from the injuries that sidelined him for the final two months of last season. And the Canadian world No 24 looked short of match fitness in his defeat to De Minaur, with a lack of consistency in his groundstrokes proving costly against the Australian. “You've got to into every match believing that you can win,” De Minaur said. “I just go out to every match the same, trying to play my game and leave it all out there. “That way you're going to get yourself into a lot of matches and get yourself a lot of opportunities. It's all about taking those small opportunities, which I feel like I did today, and it helped me get the biggest win in my career.” Also through to the Brisbane quarter-finals are home favourite Nick Kyrgios, who fought back against fellow Australian Matthew Ebden to win 6-7, 7-6, 6-2, and Ukraine’s Aleksandr Dolgopolov – a comfortable 6-1, 6-2 winner over Argentine Horacio Zeballos. In the women’s draw, Elina Svitolina maintained her fast start to the season with a 6-3, 6-1 win over Croatian Ana Konjuh in the second round. Ukraine's Svitolina took just 64 minutes to see off Konjuh and book an enticing quarter-final showdown with Britain's Johanna Konta. The world No 6 was joined in the final eight by defending champion and second seed Karolina Pliskova, who took 10 minutes less to demolish American Catherine Bellis 6-1, 6-1. "I'm playing well and I'm happy that I'm showing good tennis from the start of the year," Svitolina said. "I try to always find my good tennis out there and, you know, play well. That's the most important thing." Estonia's Kaia Kanepi, the 2012 champion, moved into the last eight with a 6-4, 6-3 win over Ukraine's Lesia Tsurenko. Belarusian qualifier Aliaksandra Sasnovich booked a quarter-final against Frenchwoman Alize Cornet when she beat Estonia's Anett Kontaveit 1-6, 7-6, 6-3.