Simpson never committed to the event at Firestone C.C. in Akron. The deadline to enter the tournament was at 5 p.m. on Friday.
The world No. 5 chose not to play in last week's British Open, instead remaining in the U.S. with his wife, Dowd, awaiting the birth of their second child. Simpson also threw out the ceremonial first pitch at a New York Yankees game last week.