Scheffler was comfortably in the lead going into the par-4 17th but made a double-bogey to finish with a 1-under 69 and overall score of 9-under.
The trio of leaders are one shot ahead of ahead of Jason Day (66) while Rory McIlroy shot a 71, leaving him only four back.
The toughest part for players was figuring out which way the gusting winds was blowing. Scheffler experienced that on the 17th.
"The tee shot, I hit exactly the way I wanted to," Scheffler said. "Somehow the wind either stops or goes back because the way my ball was flying it should have basically gotten to the middle of the fairway and I end up in the left bunker.
"Then I catch it a hair fat, and all of a sudden I'm dropping and hitting my fourth shot, and I hit the shot exactly the way we wanted to, and as the ball is flying, you get a gust into the wind, and all of a sudden the ball is not on the green.
"You can't get everyone correct. You just do your best to manage your way around the golf course."
Day had his own version of a hat trick on the front nine — three pars, three birdies, three bogeys — until hitting all the right shots for a 31 on the back to get in the hunt.
Denny McCarthy (64) and Austin Eckroat (71) were at 7-under 133, followed by Ryder Cup captain Keegan Bradley (70) and Nick Taylor (68).
When Keegan Bradley was announced as the new Ryder Cup captain in July last year, the second question he faced was whether he would consider giving himself a pick for the matches at Bethpage in September 2025.
Keegan Bradley edged Tommy Fleetwood with a birdie on the final hole to win the Travelers Championship in dramatic fashion on Sunday.
Tommy Fleetwood has a three-shot lead going into the final round of the Travelers Championship on Sunday.
World number one Scottie Scheffler and Austin Eckroat share the lead after the opening round of the Travelers Championship on Thursday.
