Johnson birdied five of the first seven holes on the back side of the Sherwood Country Club course and although he bogeyed the final hole he walked away with a one-shot lead over Matt Kuchar.
The exhibition event brings together 18 of the top players in the world.
Just five members of the elite field broke par on a course that presented more of a challenge than usual.
Johnson and Kuchar were the only players to finish under 70.
Johnson, who has been the runner-up in the tournament twice, birdied the first two holes and made the turn in 1-under. He then birdied the 10th, 11th, 13th, 14th and 16th holes. Three of those are par-5s.