Kuchar's reputation as one of pro golf's nice guys took a big hit earlier this year when word leaked out that he had paid David Ortiz US$5,000 (AU$7,000) from almost US$1.3 million (AU$1.8 million) prizemoney upon winning the PGA Tour's Mayakoba Classic in Mexico last November.

Three months later Kuchar upped the payment to Ortiz to US$50,000 (AU$72,000), but only after being pilloried on social media for his perceived stinginess.

Full-time tour bagmen usually receive 10 percent of a winner's prizemoney.

Ortiz, a caddie at the course where the event was held, stepped in because Kuchar's regular had been unavailable that week.

"I don't do the social media, so I think that helped to not see much (of the criticism)," the American told reporters on Wednesday on the eve of the Scottish Open in North Berwick.

"However, hearing from my grandmother, the things that she was hearing and talking to me about was really tough."

Kuchar with Ortiz at the Mayakoba Classic. PHOTO: Rob Carr/Getty Images.

Kuchar had initially defended his payment to Ortiz, saying that $5,000 was more than the arrangement between the pair for the week.

Describing the caddie payment as a "tricky situation", Kuchar on Wednesday recalled the conversation with his grandmother.

"Just the fact that she had called me to say, 'I can't believe what they are saying' is hard," he said.

"You do so much just to make (your family) proud and for it to go the other way is difficult."

Kuchar no doubt hopes the controversy is behind him, though judging by the fact that half of his Wednesday press conference was about that subject suggests otherwise.

The 41-year-old is part of a strong Scottish Open field headed by Rory McIlroy and Justin Thomas at the Renaissance Club.