Phil Mickelson opened the 2025 Open Championship at Royal Portrush with a 1‑under-par 70, navigating intermittent rain and firm winds in the first round. He followed with a 1-over-par 72 on Friday. That even-par score was enough for Mickelson to head to the weekend.

Phil Mickelson handed out a signed glove and ball to his playing partner Ryan Peake after the pair competed alongside each other in the opening round of The Open Championship. Peake played his way into The Open after winning the New Zealand Open earlier this year.