Memphis, Tennessee, June 8, 2012 (AFP) - McIlroy birdied three of his last four holes to equal his lowest PGA Tour round of the year. He also had an eagle, five birdies and two bogeys.
"It's nice to see my name on that part of the leaderboard," McIlroy said. "It's not nice when you're struggling to make the cut on a Friday afternoon. It was great. It's nice to be through to the weekend obviously. It's obviously even nicer to be leading and have a great chance."
McIlroy is competing in Memphis in order to tune up his game before heading to San Francisco for his US Open title defence at The Olympic Club.
He rolled in a birdie on 18 to vault ahead of three players at the TPC at Southwind.
Jeff Maggert shot a two-under 68 to move into a share of second at six-under. Maggert shared the first-round lead with John Merrick.
Maggert was joined in second by J.B. Holmes (64) and Kevin Stadler (65).
Merrick fired a one-under 69 and is in fifth place at five-under-par 135. He is tied with Chad Campbell (67) and Kevin Kisner (66).
McIlroy is playing St. Jude for just the second time after deciding a couple of weeks ago that he would head to Memphis in order to get in some extra competition ahead of the US Open.
McIlroy missed the cut last week at the Memorial. He hadn't broken par in his previous three starts, two on the PGA Tour and one on the European Tour. He missed the cut in all three starts.
McIlroy is hoping to become the first player to win a PGA Tour event then follow up the next week by taking the US Open.
But he is trying not to think too hard about that heading into his third round Saturday. His focus right now is on honing his game.
"I saw a lot of positive signs with my ball striking. Hit a lot of good iron shots and drivers. So that was something that I was really working on the last couple of weeks and feels like it's coming together for me.
"So I am excited to be in this position for the weekend. This is really what I wanted heading into next week," McIlroy said.
Leading scores on Friday after the second round of the $5.6 million St. Jude Classic (USA unless noted):
133 - Rory McIlroy (NIR) 68-65
134 - J.B. Holmes 70-64, Jeff Maggert 66-68, Kevin Stadler 69-65
135 - Chad Campbell 68-67, Kevin Kisner 69-66, John Merrick 66-69
136 - Ken Duke 68-68, Padraig Harrington (IRL) 68-68, Davis Love 68-68, Seung-yul Noh (KOR) 67-69
137 - Daniel Chopra (SWE) 72-65, John Daly 68-69, J.J. Killeen 68-69, Nick O'Hern (AUS) 70-67, John Peterson 72-65, Boo Weekley 70-67
138 - Robert Allenby (AUS) 68-70, Dustin Johnson 70-68, Paul Stankowski 69-69, Henrik Stenson (SWE) 72-66