Surprise Leader Atop The Open Championship

McIlroy called his own performance ‘stupid mistakes’, admitting his putting let him down on a course baked by England’s record heatwave.

DeChambeau, who had been dismissed by Nick Faldo as having ‘zero clue’, played a strategic round to stay in touch with the lead.

Defending champion Scottie Scheffler also opened with a promising round.

The dry, fast conditions have made Royal Birkdale an exacting test, with several big names already well off the pace.