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

Brazilian teenager Joao Fonseca stunned ninth seed Andrey Rublev in a major Australian Open shock on Tuesday as racquet-smashing 2024 finalist Daniil Medvedev narrowly avoided the same fate.

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).

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.

Russian ninth seed Andrey Rublev and Greek Maria Sakkari crashed out after first-round losses while Ons Jabeur, Daniil Medvedev, and Alex de Minaur marched ahead on Tuesday.

MELBOURNE - 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.

Three-times Australian Open finalist Daniil Medvedev allowed his frustrations to boil over in a Melbourne Park meltdown before advancing to the second round on Tuesday while Taylor Fritz made a strong start in his bid to end a 22-year Grand Slam drought for American men.

MELBOURNE – A volatile Daniil Medvedev mangled his racket in an epic temper tantrum on Jan 14, before battling through a five-set roller-coaster to stay alive at the Australian Open.

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 Thursday.