Johnson tapped in for par on the 18th for a 4-under 68 to finish at 20-under 268, breaking by two shots the record set by Tiger Woods in 1997 and matched by Jordan Spieth in 2015
Johnson shot a final-round 68 to hold off Cameron Smith of Australia and South Korea's Sungjae Im on Sunday. Justin Thomas was fourth at 276, with Rory McIlroy and Dylan Frittelli tying for fifth.