(CNN) -- Rory McIlroy took a three-shot lead into the final 18 holes of the U.S. PGA Championship in South Carolina after moving clear of the field when he returned to complete his third round on Sunday.
The Northern Irishman, one of 26 players who had to come back early in the morning after Saturday's thunderstorms, bounced back from his second-round 75 as he carded his second five-under-par 67 of the tournament.
If he can become the first golfer to maintain a final-round lead in this year's majors, the 23-year-old world No. 3 will be younger than Tiger Woods was when he won his second in 1999 at the same tournament.
McIlroy won his first major at last year's U.S. Open after taking an eight-shot lead into the final round, but he knows the pain of falling apart after blowing a four-stroke advantage at the Masters earlier in 2011.
"I learned a lot from The Masters and I think it will stand me in great stead this afternoon," McIlroy told reporters.
"That's definitely something that I can think back to and draw on some of those memories and some of the feelings I had at Congressional. At least being in that position before I'll know what to do again."
McIlroy, seeking to end a run of 16 different winners in the last 16 majors, went into the final round ahead of Carl Petterson.
The Swede, the pacesetter in the first two rounds, shot 72 to be on six-under 212 after 54 holes.
He was a shot ahead of Australia's Adam Scott, whose late collapse at last month's British Open handed Ernie Els his fourth major crown, 2008 Masters champion Trevor Immelman of South Africa and American Bo van Pelt.
Scott and Immelman carded 70, while Van Pelt went round in 67.
Woods, seeking to win the tournament for the fifth time and end his four-year wait for a 15th major title, had been the overnight co-leader along with 49-year-old Fijian Vijay Singh.
The American ended his third round five shots adrift of McIlroy in a tie for sixth with Singh -- who also posted 74 -- Steve Stricker (67) and Sweden's Peter Hanson (70) on 214.
"I battled back there this morning," Woods said. "I gave myself a chance. That's what I want, to give myself a shot this afternoon."
Three-time major champion Padraig Harrington, who won the PGA in 2008, was tied for 10th on 215 in a group also including 2010 U.S Open victor Graeme McDowell.
Defending champion Keegan Bradley was tied for 16th another shot back while 2005 winner Phil Mickelson was equal 20th on 217.