Florida: England's Justin Rose won the WGC-Cadillac Championship on Sunday by one stroke from American Bubba Watson after former world number one Tiger Woods set off alarm bells by withdrawing mid-round with injury.

The composed Rose shot a final round 70 to finish at 16-under-par while Watson, who had led by three at the start of the day, ended at 15-under after closing with a 74.

"These moments are incredible and they are few and far between as a golfer," said Rose.

"There has been a lot of work going on with my game and days like this, where it just all shows up, makes it all worthwhile."

Watson missed an eight-foot birdie putt on the last hole that would have forced a playoff but the left-handed American ultimately paid the price for four bogeys on the front nine.

Rose, who had played smart and tidy golf all week, offered a glimmer of hope to his rival when he bogeyed the 18th after driving into the rough then launching his approach over the back of the green.

The victory was the first in a WGC event for Rose and could move him into the top ten when the next edition of the world rankings are released.

Watson had driven into the trees on the 18th but, knowing he needed a birdie, produced a magnificent shot to eight feet to give himself a chance of extending the contest only to miss the putt.

"We just didn't give enough. We thought it was not going to break as much and it broke about three inches too much," said Watson.

"I still had a chance in the end so I was proud of myself for fighting, not giving up, grinding it out and never got down today."

World number one Rory McIlroy had put himself in the frame with an eagle on the par-five 12th but needed a birdie on the 18th to really put the pressure on Rose.

But the Northern Irishman's bogey left him two shots back in third place after carding 67 for the round.

After shooting a 73 and 69 in his first two outings this week, McIlroy continued his impressive run of finishes following his victory in the Honda Classic last week.

"I would have taken this after Friday, being only two-under par," he said.

"It's been a really good weekend with lots of positive. It wasn't quite the way I wanted to finish but it's still been a good week."

There was drama midway through the round when Woods, clearly in discomfort, withdrew on the 12th hole with an Achilles tendon injury prompting concern about his fitness for next month's Masters.

Woods was three-over-par for the day and seemingly out of contention to win the tournament when he abruptly called it quits, returning to the carpark then driving himself off the course.

"In the past, I may have tried to continue to play, but this time, I decided to do what I thought was necessary," he said in a statement.

South Africa's Charl Schwartzel showed good form ahead of his Masters title defense, shooting 68 to finish tied on fourth, three off the lead, with Dane Peter Hanson.

American Keegan Bradley, the PGA Championship winner last year, was in contention until fading down the stretch with bogeys on the 15th and 17th and a double on the final hole.

Australia's John Senden impressed with his flawless round of 65 pushing him up to a tie for sixth with England's Luke Donald, the world number two.

Senden's round was the equal best of the final day along with Italian Francesco Molinari who was also bogey-free in his 65.