Reed made three bogeys in a seven-hole stretch, but still managed an even-par 71 and was in good position to claim his third victory this year. He was at 6-under 207, two shots ahead of Seung-yul Noh (66), Freddie Jacobson (71) and Marc Leishman (73).
Noh finished the best score of the third round about the time leaders teed off. He wound up in the final group with Reed on Sunday.
Jacobson wasted a good start with a pair of 6s on the back nine.
Oliver Goss, in his second pro start, fell back with a three-putt double bogey. He had a 76 and was five shots behind.