Not only did Scott double bogey the famed par-three 17th after finding the water from the tee but followed with another at the treacherous par-four 18th after pulling his second shot from the right hand trees left and into the hazard.
The 2004 Players champion is now tied as the leading Australian with Day and Baddeley, their rounds of 70 leaving them three behind the leaders, William McGirt and Mackenzie Hughes, after day one.
Scott had been putting together an almost faultless round and held the outright lead at six under when his tee shot at the 17th missed the island green right, landed on the mound supporting the lone bunker and fed back into the water and set up a double bogey.
"I just a slight mis-hit it and it started cutting on the wind," said Scott. "I had to hit it good to be there and I just mis-hit it and it was pitched hole high right and spun back in the water.
At the 18th, his tee shot with a fairway wood finished right and in the trees and, from there, attempting to shape a shot over the trees, he pulled it left into the water.
"I didn't have any other shot. I dropped it into the worst lie you could imagine and I would have just chipped it outside ways into the water, I left it in the rough behind the trees, I just didn't believe there was any way I could go anywhere but there, go up over and have it cut a little bit, but it just didn't cut."
Scott was unable to get up and down to save bogey, capping off a horror finish to what had been a great day until 20 minutes earlier.
His finish once again highlighted just how dangerous the closing stretch of holes at TPC Sawgrass can be and this event, over this layout, is very much a case of it 'not being over until it is over'. He was however philosophical about the day and the finish.
"It doesn't matter whether you're leading on the first day. I'm in good shape, good first round, and hopefully get back up and have a better back nine early tomorrow morning and then work my way back up to the lead again."
Day would also stumble to the finish after reaching five under par through 11 holes before dropped shots at his 15th, 17th and 18th holes. While annoyed with his finish he is happy with his game is at present.
"I'm excited about where the state of the game is," said Day. "Obviously there's some positive stuff. It's easy to get your self out of position here, but for the most part I actually played some solid golf. I was thinking actually 7, 8-under after the second hole and I did give myself the opportunities coming in, I just, unfortunately, had a couple of mistakes.
"But that's golf and hopefully I don't make those mistakes over the next three days and actually capitalize on the opportunities that I give myself."
Baddeley too had moved to five under for the day when he birdied the 6th (his 15th of the round). Disaster would strike however when he pulled his tee shot left into the water at the par-four 7th (his 16th), which led to a triple bogey.
One behind the trio of leading Aussies is Cameron Smith at one under, and while Scott, Day and Baddeley will agonise over their finishes, Smith will be delighted with his very first competitive round on TPC Sawgrass' Stadium Course.
Rod Pampling made a solid start with a round of even-par 72, while Greg Chalmers and Marc Leishman opened with rounds of one-over par 73.
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