Padraig Harrington’s faint hopes of mounting a weekend challenge to Lee Westwood in the $5m Nedbank Golf Challenge evaporated quickly on a scorching day at the Gary Player Country Club in Sun City.

The 39-year old Dubliner arrived in South Africa hoping to ease the frustrations of an erratic season by claiming a victory worth $1.25m and a fistful of valuable world ranking points.

But the end cannot come quickly enough now after he was forced to produce one of his trademark, back nine comebacks just to shoot a level par 72 and finish the day seven strokes adrift of world number one Westwood entering today’s final round.

Oppressive heat took its toll on the 12-man field assembled at the luxury casino resort where the player finishing last is guaranteed a cheque for $250,000. As a result, Westwood posted a modest, one-under par 71 but still extended his three stroke overnight lead to five over fellow Englishman Ross Fisher (73) and South Africa’s Tim Clark (68) on 13-under par.

Harrington slipped back from third to joint fifth on six-under after a wildly erratic round that summed up his turbulent season.

Having followed a first round 66 with an untidy 72 on Friday, things were looking up when he birdied the first thanks to a glorious approach to four feet.

But the long game troubles that have plagued the Irish star all season quickly emerged and after three-putting the second from 60 feet for a par five, he sprayed the ball left and right for the remainder of the front nine, dropping shots at the fifth and sixth before taking a double bogey six at the eighth following another wayward tee shot.

His mood darkened further when he hooked his drive at the par-five ninth but was denied line-of-sight relief from the hospitality unit on that side of the fairway and was forced to chip back into play.

Out in three over 39, Harrington could have been forgiven for throwing in the towel but he somehow managed to cover the back nine in 33, picking up birdies at the 10th, 11th and 13th before finishing with five straight pars.

In the event that Tiger Woods wins the Chevron World Challenge in Los Angeles tonight, Westwood must to finish first or second today to remain at the top of the world rankings.

The vagaries of the system guarantee that the Worksop player will still finish the year as world number one but as for Harrington, the Dubliner enters his winter break tonight trying hard to focus on the positives of a season that saw him miss the cut in three of the four majors.

“If this is the worst it’s going to get, I’ll be a very happy man,” he said this week. “I’ve had one win, the Ryder Cup, plenty of top 10s. It’s been an OK year, but it’s just frustrating because I have high expectations.”