Another long day left him one round away from joining the recent youth movement on the PGA Tour.
Fowler showed some imagination with a cut 9-iron over the water to 6 feet for his first birdie of the round, and he kept bogeys off his card for the second consecutive day to shoot 3-under-par 69 to lead Tim Petrovic (68) and Ricky Barnes, who shot a tournament-best 62 while playing alongside Tiger Woods.
Fowler is at 16-under 200 and has the largest 54-hole lead at the Memorial since Woods led by six shots in 2000.
"I'm hitting the ball well," Fowler said. "I kept it out of trouble, and I knew opportunities were coming around. It was a matter of waiting for them."
Patience doesn't seem to fit with the trend toward youth.
Fowler will try today to become the third PGA Tour winner in the past six weeks at age 22 or under, joining Rory McIlroy, who won Quail Hollow two days before his 21st birthday, and Jason Day, who was 22 when he won the Byron Nelson Championship.
Experience might not be a factor in this case. The five players separated by five shots have combined for one PGA Tour victory -- by Petrovic in New Orleans in five years ago.
"I want to win against the best," Fowler said. "That doesn't change the way I play."
The largest crowd at Muirfield Village followed Woods, and the cheers were loud and frequent. They just weren't for him.
Barnes began his round by making a 40-foot birdie down the hill.
Barnes holed out a 9-iron for eagle on No. 11 to reach 7 under for the day, and he kept right on going until he had the lowest round of his career, and the best score of the week.
"I think it probably got noticed a little bit more," Barnes said. "Obviously, the cameras were probably already in our group, so they didn't need to go anywhere. I'll take a 62 anywhere, wither it's with my buddies or a Saturday at the Memorial."
For the first time since Woods returned to competition, he refused to speak to the media.
"I'm done," he said to a PGA Tour official before walking over a bridge toward the locker room, stopping to sign a few autographs at the top of a hill.
Woods, who had 69, is 10 shots off Fowler's lead.
Phil Mickelson could only manage 70, putting him eight shots back. He also declined to speak to reporters.