Phil Mickelson held off a last-day charge by Rod Pampling

American world number two Phil Mickelson sank a superb birdie on the final hole to win his second Colonial Invitational title by a shot.

After pushing his drive into the rough behind a clump of trees, Mickelson hit his second shot to nine feet before coming up with a magnificent putt.

That gave Mickelson a two-under-par 68 and a 14-under total of 266 to hold off a last-day charge by Rod Pampling.

The Australian, who also went round in 68, shared second with Tim Clark.

South African Clark birdied two of the last three holes for a five-birdie 66.

You have to take risks to win and I tried to do that Phil Mickelson

"You have to take risks to win and I tried to do that," he said.

"I'm as surprised as anybody I was able to make a three from over there. I'm thinking if I make par and get into a play-off, that would be great.

"It wasn't like it was an easy shot, but it came off. It was one of my more memorable ones."

Pampling, duelling with Mickelson throughout the day, had held a two-stroke lead after birdies and the seventh and ninth, but after Mickelson battled back, a nervous swing on the 17th effectively cost Pampling the tournament.

"I thought I was in a great position. I was obviously disheartened," he admitted.