Charlotte - Rory McIlroy drew comparisons with Tiger Woods after the Northern Irishman's stunning round of 11-under 61 at the Wells Fargo Championship on Saturday.
"Tiger was the man. Rory is up there. He's Tiger-like to me," said Will MacKenzie, who played with McIlroy during the Quail Hollow course record round that included 11 birdies.
"Guys like Jordan Spieth and Rickie (Fowler) are totally awesome, but when this guy hits it, you know who's hitting it.
"The long ball is impressive but he's got the touch to back it up. When this guy's on, he just loads (on his backswing) better than everybody. He's just stronger, a little more physically gifted."
American MacKenzie had never played with McIlroy, and he watched in awe as the world number one crushed his tee shots massive distances and took dead aim at pin after pin.
"It was phenomenal," said MacKenzie, a two-time PGA Tour winner. "He overpowers the course. He's way better than me. He's just a little bit better than everybody.
"I think he's going to become the Tiger Woods. I'm just glad he doesn't play every week."
Second-placed Simpson was impressed with McIlroy's score, though he did not see it.
Simpson, who lives next to the course, was surprised there was not more noise emanating from McIlroy's gallery.
"I didn't hear as many roars as I thought I would have, if he was doing what he was doing," Simpson said. "Good for him for playing so well."