At the age of 19, Learner Tien defeated Daniil Medvedev in a five-set thriller that finished just before 3 a.m. in Melbourne.
The final match of the day saw American Learner Tien, playing in his first major outside of the U.S. Open, upset No. 5 seed ...
World number one and defending champion Jannik Sinner roared back to surge into the Australian Open third round on Thursday ...