Darren Clarke blamed a cold putter after seeing his Open Championship defence fizzle out after two rounds at Royal Lytham.
Clarke added a second round of 71 to his opening 76 for a seven-over-par total of 147, comfortably outside the halfway cut.
"I'm disappointed, I would have liked to come here and put up a good score in defence," said the 43-year-old Ulsterman, who has struggled to reproduce anything like the form which brought him a shock victory at Royal St George's 12 months ago.
"Tee to green was okay, I just had a very cold putter again. It's not been very good for a long time. The damage was done yesterday but I gave myself plenty of chances to make it up today."
Clarke still harboured hopes of making the cut after birdies at both par threes on the front nine contributed to an outward half of 33, but he could not find any more birdies and a bogey on the 18th, where he missed a very short putt, summed up his day.
He was at least able to enjoy the warm reception of the crowds who defied the muddy conditions, admitting: "The roar coming down the last was fantastic. The crowd were wonderful to me last year and have been to me all year round. It is a pity I didn't give them anything to shout about.
"It has been an honour and privilege to be Open champion. It is a huge honour to have my name on the Claret Jug and they will be memories that I cherish forever."