Sales of the Black Fly buff skyrocketed after German world No 1 donned one at the World Golf Championships-Accenture Match Play Championship.

Vaughn Cochran, the owner of Black Fly Outfitter in Jacksonville, Florida said he was used to selling only about 10 of them a week, but sold 900 in the first six days after Kaymer graced our television screens wearing one.

"It’s the kind of advertisement money can’t buy," Cochran told the newspaper.

Cochran also said the store’s website recorded 122,000 views in less than a week.

"We’re looking at our shopping cart to make sure it doesn’t blow up," Cochran said.

Cochran is grateful for the increased exposure and is keen to pounce on the free publicity. He wants to give Kaymer a fly-fishing lesson in front of cameras at a US Tour event, but nothing has been organised yet.