Tien, 19, is the youngest man to beat a Top 3 player since 2022, and the youngest American man to do it since 2001.

American teenager Learner Tien beat top-seeded Alexander Zverev 6-3, 6-4 to move into the quarterfinals of the Mexican Open in Acapulco

Zverev, the top seed at the Acapulco Open, went down 6-3 6-4 to the 19-year-old American on Wednesday. Tien, who claimed a big win over Daniil Medvedev en route to reaching the fourth round at the Australian Open in January, came from 1-4 down to win the second set – and the match – by reeling off five straight games.