Tiger Woods withdrew from The Northern Trust on Friday morning, about two hours before he was to begin his second round of the first leg of the FedExCup Playoffs at Liberty National.

“Due to a mild oblique strain that led to pain and stiffness, I have to withdraw from the Northern Trust,” Woods said in a statement. “I went for treatment early Friday morning, but unfortunately I’m still unable to compete.”

For months, there have been ominous signs as it relates to Woods and whether he’s been healthy enough to compete. He hasn’t looked the same since he won the Masters in April, missing the cut at the PGA Championship in May and the British Open last month.

Before The Northern Trust even began, Woods stopped hitting full shots on the back nine of his Wednesday pro-am, later saying he did that for precautionary reasons because his back was stuff.

After Thursday’s opening round, Woods said he felt “a little stiff,’’ but did not offer that as an excuse for shooting a 4-over-par 75, which was the second-worst score posted in the first round among the 120 players in the field.

“I just didn’t play well,” Woods said after the round. “Just one of those things where I just didn’t hit any good shots and didn’t make any putts. Other than that, added up to a round that broke 80.”

Woods was playing for the first time since missing the cut at The Open last month at Royal Portrush, and you have to wonder whether he’ll shut it down for the rest of the season as he prepares for his captaincy in the Presidents Cup later in the year.

In his statement, though, Woods did say he remains “hopeful I can compete next week at the BMW Championship,” which is the second leg of the Playoffs and precedes the Tour Championship, which Woods won last September.