SOUTHPORT, England: Debutant Jackson Suber led The Open with a stunning five-under opening round of 65 on Thursday as fellow Americans reigning champion Scottie Scheffler and big-hitting Bryson DeChambeau also made their mark. England’s Dan Brown and South Korea’s Im Sung-jae had shared the lead after early rounds of 66 at a scorched Royal Birkdale, before Suber moved top of the leaderboard. Scheffler, bidding to become the first man since Padraig Harrington in 2008 to retain the title, carded a two-under 68 with DeChambeau a stroke better off.