Lee made six bogeys and three birdies as he slipped to a share of 136th place and he will need to turn it around tomorrow if he wants to make the cut.
Camilo Villegas has the lead at seven-under, while Webb Simpson and William McGirt are in a share of second place at six-under.
Lee came in to the tournament in 109th place on the FedEx Cup standings but could drop to as low as 116th if he was to miss the cut. The top 125 players in the rankings retain their PGA Tour card for next season and there are four tournaments left in the 2013-2014 schedule.
Manawatu's Tim Wilkinson, who is in 107th place on the FedEx Cup standings, opted not to play this week's tournament, while Steven Alker has taken a week off on the second-tier Web.com Tour and skipped the News Sentinel Open in Knoxville.
Alker, who is in 11th place on the Web.com Tour's order of merit, is all but assured of a return to the PGA Tour for next season.