Tommy Fleetwood was paid more than US$150,000 (RM611,000) in prize money from last month's Open Championship.
Imagine checking your bank account and seeing an extra thousand dollars or so mysteriously deposited overnight.
The blunder was noticed when a friend of the American Fleetwood - a Florida teaching pro in his 50s - revealed the windfall on Twitter.
Tommy Fleetwood tied for 12th at the Open Championship.
"I didn't know at first where the money came from because it just appeared as a wire transfer", the Orlando golfer told USA Today.
"It's just something I don't really look at but I'll get on top of that".
Here's how Thorner thinks the mistake took place: his friend Tommy Fleetwood played briefly on the European PGA Tour. "That's when I realized that it must be for the other Tommy Fleetwood and I quickly worked out that it was his Open winnings", Thorner, a golf coach, added. At least he can always say he won $154,000 at the Open'.
Thomas Fleetwood is a club professional based at Streamstrong Resort in Florida, who was born in 1959 and contested the European Senior Tour's qualifying school four times from 2013.
It may have been easy to miss for the more accomplished Fleetwood, whose career earnings are listed at $20.32 million on the European Tour's website.
He laughed off the incident after being asked about it following a practice round, saying: "I honestly didn't know anything about it".
'I wouldn't even know if I'd been paid or not because I don't really look.
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