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The 19-year-old Japanese wildcard beat Aleksandar Kovacevic 6-4 3-6 7-6 (9-7) in a rain-interrupted match to set up a second-round meeting with No.9 seed Daniil Medvedev.

Sakamoto, who won the boys' singles title at the 2024 Australian Open, is ranked No.164 in the world and his victory added to a remarkable collection of teenage triumphs at Hard Rock Stadium this week.

Moise Kouame, 17, beat American qualifier Zachary Svajda 5-7 6-4 6-4 to become the youngest male player to win a match in Miami and the youngest to claim an ATP Masters 1000 victory since Rafael Nadal in 2003.

Kouame also became the first player born in 2009 or later to win an ATP Tour match. Ranked No.385 in the world, the French wildcard is the youngest player ranked in the top 900 players and next plays Czech No.21 seed Jiri Lehecka.

Brazilian 19-year-old Joao Fonseca eked out a 6-4 3-6 6-2 victory over Hungary's Fabian Marozsan to set up a second-round clash with world No.1 Carlos Alcaraz, and American Darwin Blanch, an 18-year-old wildcard, overcame German Jan-Lennard Struff 6-3 3-6 6-3.

Together with Spanish 19-year-old Rafael Jodar, who beat German Yannick Hanfmann 6-4 4-6 6-1, the five teenagers reaching the second round in Miami marked the first such occurrence since 2007, when a group including the 19-year-old Novak Djokovic, Andy Murray, Evgeny Korolev and Sam Querrey , as well as Juan Martin del Potro, 18, came through the opening round.