DeChambeau got into the space of his European opponent.

DeChambeau and McIlroy made up the last group in the final round of the Masters last month.

DeChambeau carded six birdies and two bogeys in an opening four-under-par 66 on a course that lived up to comparisons with Winged Foot, the venue for his dominant US Open victory in 2020.

Bryson DeChambeau hopes next year’s venue of St Andrews will be his “golden ticket” to Open Championship glory. DeChambeau ended a difficult week at Royal St George’s on a high, carding his first sub-70 score in four Open starts with a bogey-free 65.

Bryson DeChambeau believes his “crazy overworking” brain was behind his health problems during the Masters.