The world No.1 took six on the 16th to fall one shot off the five-way lead shared by Cameron Young, Hideki Matsuyama, Wyndham Clark, J.J. Spaun and Akshay Bhatia on 10 under-par 134.
He suffered a penalty stroke after driving his ball into a bush at the Albany course in the Bahamas.
Scheffler's third shot struck another bush before flying into the fairway and he then missed a putt from distance for a bogey five.
"I did some good things out there," Scheffler told the Golf Channel after signing for a 69.
"Few too many mistakes, but overall another solid day on the course."
His rivals seized the opportunity.
US Open champion J.J. Spaun (68) converted two of his three eagle chances, Cameron Young (64) shot 30 on the back nine, Akshay Bhatia birdied the 18th for a 68, while Hideki Matsuyama and former US Open champion Wyndham Clark fired 66 and 68 respectively.
Spaun made only five eagles all season and then seized on the scoring holes. He hit a three-wood to three feet on the par-5 sixth and hit tee shot on the reachable par-4 14th that settled five feet away, both of them eagles. He narrowly missed a 15-foot eagle putt on the par-5 15th.
That allowed him to recover from a pair of bogeys on the opening four holes.
"Didn't get a great start, but salvaged a pretty decent round," Spaun said.
Bhatia, in his final tournament before getting married, saved himself at the end with a nifty par save from short of the 16th green and then a bogey on the par-3 17th when he chipped through the green and into a bunker, blasted out and made a 15-foot putt to keep it from being worse.
Scheffler is tied with Alex Noren (66) and Sepp Straka (69), with former Albany resident Justin Rose another shot back after a 68.
Billy Horschel had a 68 and was five shots behind. He missed most of this year after hip surgery and is the only player in the 20-man field who has not secured a spot in the Masters.
Horschel is at No.45 in the world ranking - the top 50 at the end of the year get into the Masters - and a solid finish could settle that.
Young produced the shot of the day on 15, chipping in for eagle on his way to a stunning 64 that also contained seven birdies and a bogey on 18.
with AP
18°C