Couples eked out his seventh Champions Tour win with a round of 3-under 69, finishing at 14-under 202 on the Fallen Oak Golf Club course.
Allen fell a bit short at minus-13 despite carding a bogey-free, 6-under 66.
Sharing fifth place one shot further back were Bill Glasson (69), Jim Thorpe (72) and Bobby Clampett (71).
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