Kamil Majchrzak defeated Matteo Berrettini 4–6, 6–2, 6–4, 5–7, 6–3 in the first round of Wimbledon on grass, pulling off a significant upset against the pre-match favourite. Berrettini, who entered with odds of 1.13, was heavily favoured to progress, but Majchrzak's odds of 7.18 proved prescient as the Polish player recovered from losing the opening set to dominate the middle stages and secure the match in five. After Berrettini took the first set, Majchrzak shifted momentum decisively, winning the second and third sets with increasing confidence before Berrettini narrowly claimed the fourth to force a decider. Majchrzak's composure in the final set proved decisive as he closed out the victory. The result marks a notable scalp for Majchrzak and signals potential vulnerability in Berrettini's grass-court credentials heading deeper into the tournament.