Tom Purtzer and James Mason share third place at 5-under-par 67, followed by Sammy Rachels and Allen Doyle in fifth at minus-3.
Morgan flew out of the gate with an eagle at the par-5 first. He mixed two birdies and a bogey on the rest of his front nine to make the turn at 3-under 33.
He tallied four birdies in his last six holes to take sole possession of first place.
Hale Irwin, the reigning Player of the Year and money leader, posted a 1-over 73 on Friday. Tom Kite, the 2002 champion, struggled in the opening round of his title defense with a 2-over-par 74.