But that changed quickly Thursday as the No. 7-ranked golfer in the world withdrew halfway through the first round because of illness.
Johnson bogeyed the first three holes, then recorded six consecutive pars before calling it quits. He won the Memphis tournament in 2012 and had been playing well of late.
He is still expected to be at the U.S. Open next week.
Ben Crane held the early lead at TPC Southwind, standing at 7-under through 13 holes.