Padraig Harrington lost his touch on the greens to trail leader Jim Furyk by four shots entering the final round of the Transitions Championship at Innisbrook Resort and Golf Club in Tampa.

The Dubliner posted a one over par 72 at Copperhead to slip back into a share of sixth place on seven under par as Furyk compiled an immaculate, four under par 67 to lead by three strokes from KJ Choi (67), Retief Goosen (70), Bubba Watson (70) and Carl Petterssen (70) on 11 under par.

Harrington said: “It was a tough day. I wasn’t very coordinated today. Struggled a bit. You know what, I fought hard on the back nine, created a lot of chances, didn’t hole the putts and that was a bit disappointing. But I was never a bit too sure of myself so hopefully a better day tomorrow.”

Harrington shot an almost faultless 65 on Friday, taking just 24 putts to lead by a stroke overnight from Pettersson, Furyk, Goosen and Watson with another 17 players within five shots of his eight under par total.

But with such a packed leaderboard, a poor third round was always going to lead to trouble and so it proved as Harrington stumbled to the turn in a sloppy one over par 37 and then undid a birdie at the 16th with a disappointing bogey at the last.

The Dubliner had made a positive start to his day with a birdie four at the 560-yard first. But he soon started to struggle and his first bogey came at the 195 yard fourth where he mishit his tee shot and came up 15 yards short of the green.

Indeed, while he saved par from 11 feet after zig-zagging his way up the par-five fifth, it was the only lengthy putt he would hole all day.

At the ninth, he hooked his three-wood tee shot deep into the trees and failed to chip in for his par after a misjudged 80 yard pitch spun back off the green.

The three-time major champion looked to have recovered his best form with the putter in round two but lost his feel yesterday and will need to improve dramatically to have any chance of winning his sixth PGA Tour title.

At the par three 13th he failed to frighten the hole from nine feet and it was a similar story at the 207-yard 15th, where he rifled a superb, six-iron to seven feet but powered the putt through the right to left break.

He finally got back to level par for the day at the tough, 475 yard 16th with a glorious 170-yard approach to just three and a half feet. But he disappointingly handed that shot back at the 18th, where he hooked his tee shot into sand, missed the green to the right and failed to hole a ticklish 17 footer for par.

Harrington hasn’t won a tour event since he claimed the US PGA at Oakland Hills 19 months ago. But Furyk is even more desperate for a win.

While he claimed Tiger Woods’ Chevron World Challenge late last year, the 39 year old former US Open champion hasn’t won on the PGA Tour since the pipped Vijay Singh by a stroke in the Canadian Open over two and a half years ago.

“It was tough to make birdies out there,” said Furyk, who has made just one bogey in 54 holes. “That back nine was playing awful difficult with some tight pins and some quick putts. I’ve holed some good putts and made some good saves but overall I’d say that my attitude has been good and I’m trying not to be so darned mechanical and just trying to get the ball in the hole and score.”

Harrington knows that it will be tough to catch Furyk, who is one of the most dogged competitors on tour.

He said: “You know, it’s obviously only one person, so that’s not so bad. I don’t want to give Jim a four-shot lead over a four-round tournament, let alone one round. There’s enough guys behind that somebody is going to shoot a good score and put some pressure on him. Hopefully it’s me.”

With thunderstorms forecast for late Sunday afternoon, the PGA TOur has opted to send the players out in threeballs off two tees from 11.45am Irish time.

Harrington goes out with Jeff Maggert and Webb Simpson in the third last group at 1.19pm (Irish) but does not feel that the change in format will favour one player over another.

“It doesn’t bother me, no. It will be the same for everybody,” he said. “Yeah, I’m not too fussed about going out early. It’s fine. Just go and do our best.”