Learner Tien celebrated his shock Australian Open victory over three-times runner-up Daniil Medvedev in true teenage fashion, seeking out a well-earned pizza after edging a five-set thriller to progress to the third round.

At the age of 19, Learner Tien defeated Daniil Medvedev in a five-set thriller that finished just before 3 a.m. in Melbourne.

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 a racket-tossing Daniil Medvedev 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).

Learner Tien became the first qualifier to claim an ATP top-five win at the Australian Open since Guillermo Garcia Lopez, who defeated Carlos Moya in 2005

Fifth seed Daniil Medvedev is out of the Australian Open after losing a five-set thriller to teenager Learner Tien in the biggest upset of the tournament so far.

Inspired American teenager Learner Tien outlasted three-times Australian Open runner-up Daniil Medvedev to reach the third round with a 6-3 7-6(4) 6-7(8) 1-6 7-6(7) victory in a late-night epic on Thursday.

Learner Tien takes down Daniil Medvedev in a thrilling match to advance into the next round at the Australian Open.