Wellington Jighere is celebrating his victory as the first African winner of English-language championship, beating over 400 contestants for the prize.
The World English-language Scrabble Players' Association awarded the prize to the 36-year-old, who donned a cowboy hat during the competition as a good luck charm.
Mr Jighere defeated 30-year-old Lewis Mackay, from Cambridge, in four games straight on Sunday.
Commenting on the historic win, Mr Jighere said he is exhausted but elated.
"It was a battle between one man and a whole continent. It was like I was borrowing the "pickability" of all the glorious pickers in the house," he said in a message posted on Facebook.
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I'll be releasing a more appropriate statement later. I really must endeavor to rest now. I've not slept well in about a week," he said, referring to the training for the competition.
Suleiman Garba, the president of the Nigeria Scrabble Federation, said the win was the result of pure hard work.
“It is a testimony of the potential of Nigeria as a country and the sacrifice and hard work of the board under my leadership," he told the News Agency of Nigeria.
"We started preparation about a year ago with seven camps which we christened Scrabble Meets to put our team in shape for the world championship and it has paid off.
"I am very proud of the Nigerian team and very proud to be Nigerian," he said.
The highest-placed Australians in the competition were Craig Beevers, placing ninth, Russell Honeybun in 31st place and Daniel Piechnick taking 55th place.
