The 24-year-old American finished three shots clear at 18 under par with a closing 68 at Kingston Heath. Johnston’s rapid rise comes just a week after his debut, where he finished tied for 42nd.

Hailing from Libby, Montana, Johnston’s win also secured him a spot at the 2025 Open Championship at Royal Portrush, alongside runner-up Curtis Luck and Marc Leishman.

Luck’s closing bogeys on the final holes sealed Johnston’s triumph, capping a remarkable week for the Arizona State alumnus.