American qualifier Learner Tien shocked the tennis world on Thursday when he upset last year's Australian Open runner-up Daniil Medvedev in a nearly five-hour, five-set match in the second round. Tien took an early two-set lead (6–3,

American teenager Learner Tien produced arguably the biggest shock of the Australian Open so far as he defeated last year’s runner-up Daniil Medvedev in five sets, 6-3, 7-6 (4), 6-7 (8), 1-6, 7-6 (7).

Daniil Medvedev is out of the Australian Open after losing to American qualifier Learner Tien in the biggest upset of the tournament so far. The 28-year-old was taken all the way to a deciding set by his teenage opponent, with the match going on for nearly five hours and ending just before 3:00am.