Ben Crane shot a 5-under 65 on Friday to open a six-stroke lead in the St. Jude Classic before heavy rain delayed play twice and forced the suspension of play for the day.
Crane birdied his final hole Thursday night for a 63 and rolled in a 44-footer for birdie to start the second round Friday morning.
He had a 12-under 128 total at TPC Southwind, matching the winning score in relation to par last year.
Carl Pettersen and Jason Bohn were tied for second. Pettersen had one hole left, and Bohn had two to play.
Davis Love III (70) and Billy Horschel (68) were in at 5 under.
Phil Mickelson and Retief Goosen were unable to start the second round.
Mickelson opened with a 67 on Thursday, and Goosen had a 66.
After a 59-minute delay because of lightning, play resumed for 13 minutes before being stopped again.
Fans were sent home and the round was suspended just before 5 p.m.