Reilly Opelka defeated Alex De Minaur 7–6, 6–4 in the first round of the Cincinnati Masters on hard court, delivering an upset against the favoured Australian. De Minaur entered as the pre-match favourite with odds of 1.24, but Opelka's commanding performance—particularly his serve-based game—proved decisive in both sets. The American secured the opening set via tiebreak before breaking clear in the second to advance comfortably. This result represents a significant statement from Opelka at a Masters 1000 event and demonstrates his capacity to trouble top-ranked opponents on hard courts, whilst De Minaur will seek to reassess his form heading into the remainder of the summer swing.