But top seed Halep is a much tougher assignment as she edges towards an eighth Melbourne title at a tournament blown wide open with the ousting of defending champion Caroline Wozniacki and second seed Angelique Kerber. French Open champion Halep struggled in her opening two matches, where she was extended to three sets in both, before finally hitting form to beat Serena's sister Venus in round three. The winner will play either seventh seed Karolina Pliskova, who won the Brisbane International warm-up, or two-time major winner and 18th seed Garbine Muguruza for a place in the semi-finals. Fourth seed Naomi Osaka is also in action against 13th seed Anastasjia Sevastova while Ukraine's Elina Svitolina takes on American Madison Keys. "I feel like I've been playing well, so things are progressing well," said the Serbian 14-time Grand Slam winner.

Source: Daily Nation January 20, 2019 22:07 UTC