Top-seeded Alex de Minaur, second-seeded Frances Tiafoe and Miomir Kecmanovic all advanced to the semifinals of the Next Gen Finals with straight-set wins Thursday.
De Minaur, who finished runner-up last year in the season-ending tournament for the top under-21 players, beat Casper Ruud 4-1, 4-0, 4-2 in just 61 minutes to finish 3-0 in Group A.
De Minaur's semifinal opponent will be Tiafoe, who defeated Mikael Ymer 4-2, 4-2, 4-2.
Kecmanovic beat Alejandro Davidovich Fokina 4-1, 4-1, 4-3 (6) and will face Italian teenager Jannik Sinner for a spot in the final.
Kecmanovic finished with a 2-1 record in Group A at the event, which features a unique format where each set is first to four games.
Tiafoe was 2-1 in Group B, while Sinner advanced by winning his opening two matches in the group.