Jason Day, the 2016 Players champion, withdrew from the tournament citing illness, the PGA Tour announced Thursday ahead of the opening round.

Day, who was scheduled to go out at 8:46 a.m. EDT with Wyndham Clark and Jordan Spieth, was replaced in the field by Danny Walker.

Golf Channel’s Steve Burkowski reported on “Live From” that Day developed a “severe stomach bug overnight” and was unable to compete.

The 37-year-old was in contention last week at the Arnold Palmer Invitational before finishing with a 74 that left him tied for eighth. His most recent win came at the 2023 Byron Nelson event.

Walker, a 29-year-old Korn Ferry Tour grad, is making his Players Championship debut.