PLAYER OF THE DAY: Karolina Pliskova - the Czech fended off four match points and rallied from 5-1 down in the deciding set to send seven-times champion Serena Williams packing with a stirring 6-4 4-6 7-5 quarter-final comeback win.

QUOTE OF THE DAY: "I was almost in the locker-room but now I am standing here as a winner. It is a very good feeling," Pliskova said after the two-hour, 10-minute battle on Rod Laver Arena.

STAT OF THE DAY: Either Pliskova or fellow semi-finalists Naomi Osaka or Petra Kvitova will rise to world No.1 for the first time on Monday.

TOURNAMENT SUMMARY: Pliskova will take on US Open champion Osaka after Kvitova plays unseeded American Danielle Collins in Thursday's first semi-final.

Australian Associated Press