Adam Scott traded a birdie for a bogey three times during his second round Friday at the PGA Championship, but it was his other two birdies that kept him atop the leaderboard midway through round two at Oak Hill.
The Masters champ carded a 2-under 68 to finish two rounds at 7-under-par 133.
While Scott was remaining atop the leaderboard, U.S. Open champion Justin Rose was moving closer to the lead. Rose, who played alongside Scott and Phil Mickelson, played the back nine in 2-over 37.
Around the turn, Rose poured in six birdies for a 6-under 29. Added up, Rose carded a 4-under 66, which moved him into second place at minus-6.
Former major champions Webb Simpson (64) and Martin Kaymer (68) are the next closest to the lead and in the clubhouse. That duo finished two rounds 4-under 136. Simpson's 64 matched the course record that Ben Hogan first set in 1942 and Curtis Strange matched in 1989.
Scott Piercy and Jason Day both carded 71s to end 36 holes at minus-2, while Lee Westwood (73) and Zach Johnson (70) were the final two players from the morning wave to finish in red figures at 1-under 139.
Mickelson had a lone birdie on his opening nine, then two bogeys on his way into the clubhouse for a round of 1-over 71. He finished two rounds at plus-2.
The morning wave, which was also the late wave on Thursday, had the worse of the weather through two days. On Thursday afternoon, they had to sit out a 70- minute weather delay.
On Friday morning, steady rain fell for a significant period of time. The morning rain totaled 0.55 inches, which raised the total over the last two days to 0.92 inches.
Scott started on No. 10 and birdied his opening hole. He later tallied birdies at 13 and 16 to move to 8-under for the championship. Scott stumbled to a bogey on the 17th.
Around the turn, the Australian birdied the second, but gave that stroke right back with a bogey on the par-3 third. Scott birdied the next par-3, the sixth, but missed the green at seven and failed to get up and down for his par.
Scott parred the last two holes to lead Rose by one.
Rose started with bogeys on the 10th and 11th to fall to even-par for the championship. He birdied the short par-4 14th, but gave that stroke back with a bogey on the 18th.
The Englishman caught fire around the turn. Rose birdied the first, and followed with birdies on the second and third. He made it four birdies in five holes with a birdie on the fifth.
Rose closed his round with birdies at eight and nine to end one back.
The afternoon wave is well underway with Robert Garrigus moving into a share of the lead as he is 4-under par through nine holes to reach 7-under for the championship.
Jason Dufner holed out for eagle on the second and also has two birdies to reach minus-6. Paul Casey and Matt Kuchar are at minus-5.
Four-time champion Tiger Woods bogeyed the second and is 2-over par for the championship. He parred one and three.
The cut line currently stands at plus-3. If it remains there, Nicolas Colsaerts, Bubba Watson, Luke Donald, Geoff Ogilvy, Nick Watney and Lucas Glover would be among those missing the cut. If the cut moves back to plus-2. Brandt Snedeker and Gary Woodland would be among those missing the weekend.
Woody Austin ended at plus-4 after carding a 75 in round two. That 75 included four penalty strokes. Austin discovered on the third hole that he had too many clubs in his bag, and he was assessed a 2-shot penalty for the first and second holes for completing those holes with an extra club in his bag.