Daniil Medvedev defeated Kasidit Samrej (6–2, 4–6, 3–6, 6–1, 6–2) in the first round of the Australian Open, but as you can tell, it was not all smooth sailing for the fifth ranked player in the world.

Learner Tien has become the youngest American man to reach the Australian Open’s third round since Pete Sampras in 1990.

In a stunning Australian Open upset, 19-year-old American qualifier Learner Tien knocked out former finalist Daniil Medvedev in a thrilling five-set marathon.