Diego Schwartzman joked after his Australian Open third-round win on Friday that he knew more about the diminutive Yoshihito Nishioka than Novak Djokovic, but the Argentine is well aware that beating the 16-times Grand Slam will be a tall order.
Schwartzman heads into his fourth meeting with Djokovic on Sunday having never defeated the Serb, who looked in ominous form in his thumping 6-3 6-2 6-2 win over Nishioka to stay on course for an eighth title in Melbourne.
In other Sunday match ups, Swiss world number three Roger Federer, who came back from the brink to edge past Australian battler John Millman in five sets, will hope his fourth-round meeting with Marton Fucsovics of Hungary will be physically less demanding.
Double Wimbledon champion Petra Kvitova has scythed down opponents without dropping a set in the tournament so far and the seventh seed will look to produce yet another ruthless display against Maria Sakkari of Greece.
Top seed Ash Barty will resume her quest to become the first homegrown champion at the tournament since 1978 when she meets 18th-seeded American Alison Riske while Tunisian sensation Ons Jabeur takes on Wang Qiang who knocked out Serena Williams.
