Shane Lowry has opened up on the crisis of confidence that left him under-motivated in the run up to this week's US PGA Championship.

The Offaly golfer, currently ranked 83rd in the world, tees off at Quail Hollow Thursday, coming off a pair of missed cuts - at The Open and the RBC Canadian Open.

"I left Canada a few weeks ago very disheartened with my whole game and last week I was struggling to find interest to go and practise," said Lowry on Wednesday.

Having won the 2015 WGC Bridgestone Invitational and finished second at last year's US Open, having led after 54 holes, Lowry came into this season with high hopes that have not been realised.

His best result on the PGA Tour this year was a tie for 14th at the AT&T Pebble Beach Pro-Am, but an encouraging sixth at Wentworth in May, solid US Open outing and tie for 20th at the Dubai Duty Free Irish Open had the 30-year-old hoping for good things as he headed for Royal Birkdale.

Unfortunately the Clara native missed the cut at The Open following a 72 and 78 left him at 10-over following his opening two rounds. There was no return to form a week later, as he again missed the cut - this time in Ontario.

The 2009 Irish Open champion admits the back-to-back disappointments last month left him feeling under pressure to rescue something from his summer.

"I was pretty down about the whole thing because I felt I had been going well heading into the Open and then, all of a sudden, the Open and Canada I had two bad weeks and then all of a sudden I almost feel like my summer is behind me and I feel like I am chasing it a bit this week," said Lowry, who tees off at 7.25am North Carolina time (12.25pm Irish time) tomorrow, alongside Australian Stuart Deane and Pablo Larrazabal of Spain.

A naturally indefatigable character, Lowry was talking a good game ahead of the final Major of the season.

"I kind of took some time to reflect last week. Look, I am just here this week. I am going to give it my best and I was happy with how I played today.

"I think if I can play towards that and sharpen up my short game a little bit I would do okay here this week. There is no reason why I can't do okay, it is not that far away for me. I just need a few things to sharpen up."

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