Alex De Minaur defeated Taylor Fritz 7–6, 6–3 at the ATP Tour Finals on hard court in the round-robin stage, posting a significant upset against the pre-match favourite. Fritz, who entered with odds of 1.39 to De Minaur's 3.27, was unable to sustain the form that had brought him to the year-end championship. De Minaur secured the opening set via tiebreak before breaking clear in the second, demonstrating control when it mattered most. The result represents a notable scalp for De Minaur in the elite eight-man field and strengthens his position in the round-robin standings.