Rising tennis star Learner Tien scored the biggest win of his career when he defeated World No.2 Alexander Zverev at the Mexico Open on Wednesday, etching his name in the history books in the

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.

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