Verplank was 9 over par for the tournament when he withdrew after nine holes Friday. He shot 75 in the first round Thursday.

The 48-year-old Verplank finished tied for fourth at last year's PGA Championship but hasn't been much of a factor this season.

Verplank withdrew from The Players Championship in May because of an injured left wrist, and he had played only one PGA Tour event since then, missing the cut at the St. Jude Classic in June.

He played the back nine Friday and made two bogeys and two double bogeys, then stopped before playing the front.