Fitzpatrick made light of the cold, breezy conditions to card a superb 67 on Saturday.
It is the first time in his career that Woods has withdrawn from a major.
The Miami Heat took Game 3 of the Eastern Conference Finals on Saturday in a 109-103 win, as an injured Jimmy Butler missed the second half.
Without a PGA Tour win, Mito Pereira leads the US PGA Championship heading into Sunday's final round after a one-under 69 on Saturday.