Following elbow surgery in July, Zheng secured her initial victory against a top-20 competitor by defeating American 15th seed Madison Keys.
Out of eight encounters with Olympic champion Zheng, Sabelenka has emerged victorious in seven.
Elena Rybakina, seeded third, advanced effortlessly to the round of 16 after defeating Ukraine’s Marta Kostyuk in straight sets, 6-3, 6-4.
Rybakina from Kazakhstan is set to face Australian qualifier Talia Gibson, who eliminated another seeded competitor, 18th seed Iva Jovic, with a commanding 6-2, 6-2 performance.
Having previously reached the quarter-finals at Indian Wells, Gibson triumphed over former world number one Naomi Osaka during the second round of the Miami tournament.
Jessica Pegula, the American fifth seed and last year’s finalist against Sabalenka, required a mere sixty-six minutes to secure a 6-2, 6-2 win against Canada’s Leylah Fernandez.
Jelena Ostapenko of Latvia, who was the Miami runner-up in 2018, mounted a comeback to defeat Italian seventh seed Jasmine Paolini with a final score of 5-7, 6-2, 7-5.
Ostapenko’s next opponent will be American world number 45 Hailey Baptiste, who previously overcame Ukrainian ninth seed Elina Svitolina 6-3, 7-5.
