Rain halted play for over three hours early in the day and only two of the afternoon groups were able to complete their opening rounds. The first round will continue at 7:30 AM local time.
Stuart Appleby shot a 6-under-par 66 to share second place with Carl Paulson and Tom Pernice, Jr. Paulson has played 16 holes, while Pernice is through 15.
Couples, who has four top-15 finishes in his last five tournaments, began his day on the back nine of the Redstone Golf Club. After a pair of pars, he got going with a 15-foot birdie putt at the par-5 12th.
He then notched back-to-back birdies from the par-4 14th. Couples dropped a shot at the par-four 16th to make the turn at 2-under.
On the front nine, Couples really caught fire. He missed a birdie chance at the first, but came back by making a 15-footer for birdie at the second. He made it two straight with a 30-footer at the next.
Couples capped a run of three straight birdies when he sank a five-footer at the par-4 fourth. He later made back-to-back birdies from the seventh to take the outright lead. With a chance for a two-stroke lead, he missed a birdie at the ninth.
'Today was one of those rounds,' said Couples. 'I made the turn at 2-under and missed a birdie chance at No. 1 from 35 feet. I was kind of kicking myself, but then I had a nice string of birdies.'
Appleby got off to a fast start but then cooled considerably. He birdied the par-5 first when he two-putted for 40 feet. He followed that with an eight- footer for birdie at the next. Appleby parred the next nine holes.
He birdied the par-5 12th when he two-putted from the fringe. Appleby continued his strong play on the par-5s as he eagled the 15th, his next par-5, from 25 feet.
However, the Australian could not continue his momentum as he bogeyed the next when his second shot flew the green and he was unable to get up-and-down. He recovered that stroke by making a 20-footer for birdie at the next. Appleby capped his round with a short birdie putt at the last.
'I didn't drive the ball that well,' said Appleby. 'It's definitely been a drought the last few months. I am certainly not playing at the level that I want to play and know I can play.'
Peter Jacobsen, who designed this course with Jim Hardy, is tied for fifth after shooting a 5-under-par 67. He is tied with David Berganio, Jr., Jose Coceres, defending champion Vijay Singh, David Peoples and Briny Baird. Peoples has completed 15 holes, while Baird is through 11.
'No wonder (Jack) Nicklaus wins so many tournaments because he designed so many courses,' said Jacobsen. 'If I had known this is how it goes, I would have got involved in golf course design long ago. It felt great.'
Adam Scott and Andrew Magee are among a group of 12 players tied at 4-under-par 68. Also in that group are Brandt Jobe, Ian Leggatt, John Morgan, Deane Pappas, Rory Sabbatini and Patrick Sheehan, who are all finished. Rod Pampling and Paul Stankowski are also minus-4 but have only played 16 holes, while Jay Haas has completed 15 and Olin Browne is through 12.