Clarke made his first cut in eight events a fortnight ago

Clarke made his first cut in eight events at the Buick Open two weeks ago and he is back in action this week at the Scottish Open.

"I've been putting the wrong shafts in my irons for three years," said Clarke.

"I came home and changed them and straight away my iron play turned around. Hopefully that's going to stand me in good stead."

Clarke added that a couple of strokes with his new irons were enough to convince him he had made the right move.

"I had two shots when they had been reshafted and the difference was massive," said the Northern Irishman.

"My irons had been going right and left and too high. You would think I would be smart enough to figure it out myself after about three years but I wasn't quite clever enough."

Clarke, without a tournament victory since the 2005 Taiheiyo Masters in Japan, said he was now feeling much happier on and off the course.

The 38-year-old, whose wife Heather died of cancer last year, said it had taken him a long time but that he had rediscovered his desire for golf.

"My game has been struggling, my boys have been struggling, but things have been turning around a little bit," said Clarke, who has played on five Ryder Cup teams.

"It seems like things are starting to finally get back to normal again and consequently I feel happier about what I am doing.