Couples finished the day at 15-under-par 195 -- a three-round record for the major Champions Tour tournament -- in seeking his third career major victory.
Jumping into second place two shots back at minus-13 was Kenny Perry, whose 7-under 63 tied the lowest third-round score at the event.
Holding sole possession of third place at 11-under 199 was Duffy Waldorf (66).
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