Reilly Opelka defeated Holger Rune 4–6, 6–3, 7–6 in the first round of the Miami Masters on hard court on 22 March 2025, upsetting the pre-match favourite. Rune, seeded higher in the betting odds at 1.46, struggled to maintain consistency through three sets, losing the opener before recovering in the second. The match went to a deciding tiebreak, which Opelka claimed to secure a notable upset victory. The American's ability to convert under pressure in the third set proved decisive, particularly in the tiebreak where Rune could not close out the contest despite having opportunities. This result represents a significant scalp for Opelka early in the tournament and raises questions about Rune's form heading into the latter stages of the Miami event.