Darren Clarke. Photo Eoin Clarke/www.golffile.ieDarren Clarke confessed that he’s struggling to go the distance as he battles a niggling groin injury at Augusta National.

The Open champion, 43, walked in after playing the back nine in practice and then decided not to take part in the annual Par-Three contest.

Frustrated by his injury, Clarke said: “Augusta is a tough walk at the best of times and the groin is still sore. There is nothing I can do just apply an ice pack and rest.”

Clarke was the last player to register on Tuesday before playing the front nine later in the evening.

And there must now be serious doubts about his ability to last even 36 holes on a hilly Augusta National course, despite his intention to “eat painkillers” this week.

Unsure if he would be able to practice again last night, he said: “I’m not able to practice as much as I would like, put it that way.

“I am struggling to walk so I don’t think an another nine holes is going to do me any good.”

Making his first Masters appearance for five years, the Ulsterman is bitterly disappointed to return to Augusta with an injury.

Asked if there was ever a doubt about his participation, he said pointedly: “It’s the Masters!”

He hasn’t noticed the subtle changes to the course since he shots rounds of 83 and 71 to miss the cut in 2007.

He added: “The course is just the same as what it was the last time I was here.”