He ended up two shots behind 27-year old Pan, who shot a four-under 67 to win his maiden PGA Tour title by one stroke from Matt Kuchar, who shot 67, on 12-under par

After briefly moving two shots clear after birdies at the second, fifth and sixth, Lowry was shocked to miss a three footer for par at the ninth.

But it was a double bogey six at the 12th, where he took four to get down from 35 yards left of the green, that all but scuppered his title chances.

While he fought back with a birdie from 30 feet at the par-three 14th, he couldn’t find birdies down the tough finishing stretch and had to settle for his first top-10 finish since his Abu Dhabi HSBC Championship win in January and a cheque for $358,800.

“I personally feel like it almost got away,” said Lowry, who teams up with Pádraig Harrington for this week’s Zurich Classic of New Orleans. "I'm a little bit disappointed right now but this was my best week in quite a while, so there are many positives to take from this week.

"After coming so close, it's hard to describe what it's like, but I'm sure I'll get over it and move on to next week.

“It’s the best I've hit the ball in a while. I've already won this year, so this is my ninth tournament and I’ve had another great chance to win, so I suppose I'm doing things right."

"Like I said, I'm looking forward to next week and the rest of the season."

Overnight leader Johnson slipped to a disappointing 77, dropping seven shots in a nightmare five-hole stretch from the 11th to finish tied 28th on four-under with playing partner Ian Poulter tied 10th after a 73.

“To have a W on the PGA Tour, it means everything,” said Pan, who didn’t speak English when he moved to the US and attended IMG Academy in Florida. “It means to the world to me. That’s why I came to the US and went to college. Dream come true."

He was two shots clear with four to play but after taking six at the par-five 15th, he birdied the 16th and finished with two gutsy pars to claim the $1,242,000 winner’s cheque, hitting a glorious 180-yard approach to 18 feet at the last, where he lipped out for birdie.

As for Power, who was ranked a lowly 189th in the FedExCup standings after missing 11 of his first 15 cuts this season, the 32-year old from West Waterford was thrilled to close with a four-under 67 and finish tied sixth on nine-under.

Projected to move up to 141st in the FedExCup standings with the top 125 at the end of the season keeping their cards, he’s hoping this week will be a stepping stone to greater things.

“I didn’t make to many mistakes and my short game was pretty good all week,” Power said after his first individual top-10 finish for 13 months earned him $231,150.

“I made one bogey on one of the easier holes, which was disappointing but overall it was a tricky day so I can’t complain too much.”

Out in one-under par after following birdies at the second and fifth with a bogey at the ninth, he birdied the 13th and 15th before making a 60 footer for his fifth birdie of the day at the 16th.

“I can take a lot from this,” said Power, who missed seven cuts in a row either side of Christmas. “The last four or five tournaments have been much, much better. I started to find something at The Players (tied 35th) and it’s been encouraging.

“A week like this is great. It gets me kickstarted. I’m obviously not where I want to be but it’s a step in the right direction.”

Graeme McDowell, the 2013 champion at Harbour Town Golf Links, had an expensive finish when he three-putted the 18th from just 12 feet for a double-bogey six and signed for a two-over 73 that left him joint 48th on one-over par.