Woods will play on the PGA Tour for the first time since February when the event begins Thursday at Muirfield Village in Ohio.
MORE: Ryder Cup postponed to 2021
Johnson, who has missed the past two tournaments after winning the Travelers Championship, has no doubt the 15-time major champion will be ready.
“Obviously it’s tough to simulate competition, but if anybody will be ready to play after not playing for five months, I think Tiger will be,” he told a news conference.
“I don’t think he would come back and play this week if he wasn’t ready.”
Johnson, the world No. 4, said the biggest challenge after a break was being mentally switched on.
“For me it’s mostly the mental game, really, is the hardest, just to get into competition mode and to remember you’re playing in a golf tournament and not just at home playing for fun,” he said.
“You know, just to obviously play in a competition, you think a little bit differently than you do when you’re just out there slapping it around with your buddies.”
