Phil Mickelson leads the club on Day 2 of the US PGA Championship after playing his way to a first major title in eight years.
The 50-year-old finished with five birdies in his last nine holes to score a 69-under-par on Friday, taking him to five under overall.
This puts the two Americans on the sidelines after the early starters have completed their rounds on the Kiawah Island Ocean Course.
Ian Poulter worked his way through the mix before fading to finish at normal level.
Mickelson’s closest clubhouse challengers are three-under-par South Africans Branden Grace and Christiaan Bezuidenhout.
Grace led until the 16th, but sent her tee shot to the dreaded 223-yard par-threes 17th into the water for a double bogey, then bogeyed the 18th for a round of 71.
Rory McIlroy, Bryson DeChambeau, Brooks Koepka and Justin Thomas are all among the latest starters.
Mickelson won the Wanamaker Trophy at that event in 2005, but the last of his five major titles came at the Open in 2013 and his most recent victories came on the PGA Champions Tour.
World number 115 says he tries to improve his focus and stay more “present” by practicing meditation and other exercises to increase his focus.
That work came to fruition on Friday as “ Lefty ” improved throughout his round and rolled in a 22-foot birdie on the last to fully take the lead as Grace fell back.
Having started in the 10th, he hit the turn one over, before a sensational streak of five birdies saw him play the last nine in 31 strokes.
“You’re going to be doing a lot of bogeys here, but if you can manage to prevent doubles that’s an important thing,” said Mickelson, who is looking to become the first player aged 50 or over to hold at least a share of the 36-hole head since Sam Snead in 1966.
“Physically, I have been able to hit the punches I want to hit as well as ever, but I haven’t been so sharp mentally and I haven’t been able to visualize too. It’s (meditation) has been a big part of myself, able to take some of these shots.
“It gets harder and harder as I get older to concentrate for longer periods of time, so I tried to lengthen my focus – maybe I could go play 36 or 45 holes to try and focus more. long as only 18..
“I have tried to lengthen the time I can meditate, especially on the rest days, and I am seeing progress and I can focus longer throughout the lap and as I have it. done, my scores improved. “
Poulter slips after a quick start
Poulter’s tournament threatened to fall apart on day one as he dropped five shots in as many holes after a promising start to head to the second round with two more.
It was a similar story for the Englishman on Friday as he dropped four shots in his last six holes.
The 45-year-old, who has never won a major, pieced together a confident opening nine that included two birdies and an eagle in the seventh par-five.
When the world number 67 birdied back to back after the turn, he moved into one of Grace’s firsts and had six pennies for the day after 11 holes.
A bogey followed at 13 after a temperamental training and Poulter then hit his tee shot at par 3 14th to give up successive strokes.
Another bogey on the 16th par-five for 608 yards saw him come back to a sub and this was immediately followed by a drop shot to 17 after a wild tee shot and he eventually signed for a two under 70.
American Jordan Spieth, in pursuit of the career Grand Slam, is on the cut-line four-on-par while world number one Dustin Johnson is expected to miss the weekend at six more.