Raphael Collignon upset Casper Ruud 6–4, 3–6, 3–6, 6–4, 7–5 in the first round of the US Open on hard court on 27 August 2025. The result constituted a major upset, with Ruud entering as a heavy favourite at odds of 1.16, whilst Collignon was priced at 6.11. The match proved competitive throughout, with momentum swinging between the players across five sets. Ruud claimed the opening set and led in the third, but Collignon recovered to win the second and third sets, before Ruud levelled at one set apiece. The decisive fifth set proved decisive, with Collignon prevailing 7–5 to secure an impressive first-round victory. The upset win marks a significant scalp for Collignon at a Grand Slam event.