Defending champ Jannik Sinner drops set for first time since October, but rallies for win; American Danielle Collins plays villain while advancing.

Defending champion Jannik Sinner's consecutive-sets streak ended in the second round of the Australian Open on Thursday night, but he advanced with a 4-6, 6-4, 6-1, 6-3 victory over wild-card entry Tristan Schoolkate.

Jannik Sinner, defending his Australian Open title, shares an emotional update about his coach following his second-round victory as he prepares for a third-round clash with Marcos Giron.

Jannik Sinner has announced that he will part ways with his coach Darren Cahill at the end of the season. The Australian, who joined Sinner's team in July 2022, will conclude the 2025 campaign before stepping back from full-time tennis.

Jannik Sinner has started his Australian Open title defense with a challenging win over No. 35-ranked Nicolas Jarry.