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

Daniil Medvedev could be set to leave the Australian Open with over $200,000 in fines and bills after defying the rules again on Friday morning after his shock loss to Learner Tien. The American qualifier pulled off an extraordinary 6-3 7-6 (7-4) 6-7 (8-10) 1-6 7-6 (10-7) win over Medvedev in 4 hours and 49 minutes on Margaret Court Arena.

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.