John Daly will not play next month's British Open in Northern Ireland if he is not allowed to ride a cart, the 1995 champion said on Thursday.
Speaking after the first round at the PGA Championship, Daly said he had applied to the R&A organising body for permission to ride at Royal Portrush for the July 18-21 tournament and was awaiting a reply.
Daly, who has an arthritic right knee and walks with a slight limp, is riding a cart at the PGA Championship under the Americans with Disabilities Act (ADA).
"Ireland is big on the ADA like most countries should be," Daly told reporters at Bethpage Black.
"Trust me, if I could walk I would rather walk. I feel like I always have played better when I walk.
"I'm not one who wants to ride all the time. It's just something, if I don't I'm not going to be able to play, not going to be able to finish."
Daly said it had been almost embarrassing riding a cart at Bethpage Black, where he limped and puffed his way around the long and hilly course on Thursday.
"It's very awkward, to a point it's almost embarrassing, but I love the PGA, and I feel like as past champion I belong to play ... I feel obligated," the 1991 champion said after shooting five-over-par 75.
Daly walked two years ago at Royal Birkdale, where he missed the cut, and did not play last year.
He ruled out walking at Portrush.
"I wouldn't be able to," said the 53-year-old American.
"Hard pan (surfaces typical of links courses) is better to walk on. I would probably get nine holes and that would be about it.
"Out here (I could walk) maybe four before I couldn't even swing."