In the other Group B match, second-seeded Frances Tiafoe of the United States — who lost to Sinner on Tuesday — beat Ugo Humbert of France 4-2, 4-3 (5), 3-4 (4), 4-1. Top-seeded Alex de Minaur of Australia, who was runner-up last year, leads Group A after defeating Miomir Kecmanovic of Serbia 4-1, 4-3 (4) 1-4, 4-0 to make it two wins out of two.
Kecmanovic is 1-0 in the tournament as is Norwegian Casper Ruud, who beat Alejandro Davidovich Fokina of Spain 3-4 (2), 4-3 (2), 4-2, 3-4 (2), 4-1. This is the third edition of the year-end event for the best under-21 players.
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