Sluman's performance on the back nine allowed him to go into the clubhouse with an 8-under-par 64, good for 11-under-par 133 after 36 holes at Fallen Oak.
He was joined there by Couples, who racked up six birdies but also notched four bogeys to finish with a 70 Saturday.
Both golfers also had to finish their first rounds earlier in day after a weather delay of more than 4 hours set the tournament back Friday.
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