American Ben Crane defied recent poor form to post a bogey-free seven-under 63 and surge to a two-shot lead in a weather-affected first round of the FedEx St Jude Classic in Memphis.
Crane, a four-time winner on the US tour but without a title since 2011, sat alone as the clubhouse leader after darkness halted play with 60 players still to complete their rounds due to an earlier storm delay.
Fellow Americans Peter Malnati (65) and Billy Horschel, five-under through 16 holes, shared second at five-under.
Major winners Retief Goosen (66) and Zach Johnson (15 holes) were joined by Joe Durant (66), Jason Bohn (14 holes) and Australian Stuart Appleby (17 holes) in a tie for fourth at four-under.
Phil Mickelson, a runner-up last year, started his tune-up for the US Open with a solid 67, leaving him in a tie for ninth.
Padraig Harrington, who has failed to qualify for the US Open for the first time since the turn of the century, made a two-under 68 to start promisingly.
Playing the back nine of TPC Southwind first, Crane started modestly with birdies on the 11th and 16th holes before making his move at the turn.
Three birdies on the trot to start the front side and two to finish sent the 38-year-old to the top of the pile, unfamiliar ground for Crane in recent times.
Since a tie for ninth at the Humana Challenge in January, Crane hasn't finished better than a tie for 32nd and missed five of his last seven cuts leading in.
Malnati, a 26-year-old rookie coming off the secondary web.com tour, was another surprise packet given he has missed the cut on eight of his 11 appearances on tour this year.
His 65 equalled his career low on tour and was his first round in the 60s since early March in Puerto Rico.
"There have been some negative thoughts bouncing around in my head for most of the year but in the last couple of weeks I've kind of gotten it turned around," said the Tennessee resident, who sits 172nd on the FedEx Cup points list.
"I expected to come out and play well so it was great. I am really trying hard to really think about just playing golf and having fun.
Mickelson, who will attempt to complete the career grand slam in the US Open next week was treading water at one-over through 11 holes before making birdies on four of his last seven to push right into the mix.
Given his focus was finishing off rounds after letting them slip in previous tournaments the 43-year-old was pretty pleased.
"This was what I was hoping for and what I was really hoping to work on this week," Mickelson told reporters.
"I had a nice solid round going, not too many birdies, not too many bogeys but to finish off birdie-ing three of the last four makes it a great round and it is exactly what I need to do."
Defending champion Harris English struggled to a 73.