Graeme McDowell and Matt Every posted matching 5-under 66s on Thursday and share the lead after the opening round of the Heritage.
McDowell, the 2013 champion, has made three cuts in his last six worldwide starts and his best finish was a share of 36th in Malaysia. Every's only top-25 finish this season came at Bay Hill, where he won his second straight Arnold Palmer Invitational title.
Sang-Moon Bae opened with a 4-under 67 at Harbour Town Golf Links and is alone in third place. Defending champion Matt Kuchar carded a 3-under 68. He was joined in fourth place by Kevin Kisner, Morgan Hoffmann, Scott Langley and Cameron Smith.
Johnson Wagner, who lost in a playoff at the Houston Open, shot 2-under 69. Among the 12 players he shares ninth place with were Pat Perez, Ian Poulter and former Open Champion Louis Oosthuizen.
Masters winner Jordan Spieth struggled throughout the day and posted a 3-over 75, which left him tied for 93rd place. Spieth carded a double-bogey, two bogeys and a birdie in his round.