Sluman's round was highlighted by an eagle at the par-4 fourth, where he holed a 9-iron approach.
"The longest putt I made was 3 feet," said Sluman, who won six times on the regular PGA Tour. "If I'm going to have a chance to contend in the golf tournament, I've got to make some putts over 3 feet."
Jay Haas, Steve Lowery, Mark O'Meara, Bill Glasson, Bobby Wadkins, Peter Senior and Ted Schulz shared sixth place at 69. Defending champion David Eger shot a 75.