Well, this is unfortunate. Tiger Woods, who seemed to be well on the way to recovering much of his tournament-winning form, abruptly withdrew from the WGC-Cadillac Championship Sunday afternoon after 11 holes.

He left the course after unleashing a 321-yard drive at the 12th. He was then transported straight from the course to his courtesy car, a scene viewers watched via blimp. Woods offered a brief comment on the injury: "left leg," which could encompass an entire range of problems. Most ominously, Woods has had surgery after surgery on his left knee.

Woods had played well enough this weekend, carding rounds of 72, 67 and 68. He was, however, 3-over through 11 on the day.

Later, Woods released a statement: "I felt tightness in my left Achilles warming up this morning, and it continued to get progressively worse. After hitting my tee shot at 12, I decided it was necessary to withdraw. In the past, I may have tried to continue to play, but this time, I decided to do what I thought was necessary."

[Related: Rory McIlroy comes up short at Doral but proves he's got stamina]

This injury could not come at a worse possible time for Woods. He's committed to play in the Arnold Palmer Invitational at Bay Hill as a tuneup to the Masters in April. If he was going to get into Augusta-winning shape, now was the time to do it.

More on this as it develops.

-Follow Jay Busbee on Twitter at @jaybusbee and on Facebook here.-

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