Rory McIlroy has revealed how Tiger Woods - who withdrew from this week's Arnold Palmer Invitational on Monday - was receiving neck treatment as long as two weeks ago during the WGC-Mexico Championship.
"I hope he's okay," said McIlroy, the tournament favourite and defending champion.
"I saw him in Mexico getting treatment before and after he played and he did have some tape on sort of his upper back, so he was dealing with it back then as well."
Woods, 43, is a record eight-time winner at Bay Hill but withdrew from one of his favourite tournaments of the calendar year after citing a neck strain earlier in the week.
"Unfortunately due to a neck strain that I’ve had for a few weeks, I'm forced to withdraw from the API," Woods wrote.
"I’ve been receiving treatment, but it hasn't improved enough to play. My lower back is fine, and I have no long-term concerns, and I hope to be ready for The Players."
The 14-time major champion still remains in the field for next week's Players Championship, which he has won twice.