USA wildcard Learner Tien has stunned the world by upsetting last year's runner-up Daniil Medvedev after a gruelling five-set marathon.

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

The 19-year-old who was a late qualifier to the Grand Slam secured the biggest win of his young career on Thursday

Last year's runner-up Daniil Medvedev was dumped out in the Australian Open second round early Friday morning by 19-year-old qualifier Learner Tien in a massive Melbourne shock.In his debut Australian Open,

The 4-hour, 49-minute contest had a bit of everything, including — hard to believe — a six-minute rain delay that interrupted play shortly before 2:30 a.m. with Tien serving at 5-all, 15-all in the fi

On his Australian Open debut, Learner Tien stunned Daniil Medvedev 6-3, 7-6 (7/4), 6-7 (8/10), 1-6, 7-6 (10/7) in a nailbiter and faces France’s Corentin Moutet in the next round.

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

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).

Learner Tien, a 19-year-old qualifier from California, became the youngest American man to reach the Australian Open's third round since Pete Sampras in 1990, upsetting Daniil Medvedev in five sets on Thursday.

Teenage qualifier Learner Tien stunned last year's Australian Open runner-up Daniil Medvedev in an epic match ending at nearly 3:00 am Friday after defending champion Jannik Sinner roared back to take his place in the third round.