A West Australian man is counting his lucky stars after an accidental bet saw him end Melbourne Cup Day one quarter of a million dollars richer.

Josh Baker, a 27-year-old from the small town of Bakers Hill in Western Australia, thought his Sportsbet app was malfunctioning when it suddenly displayed a balance of $240,000 on Tuesday afternoon.

Mr Baker had put most of his money on fifth-placed Who Shot the Barman to take out the main race, only to be beaten by Almandin.

But the young punter had also placed a number of smaller bets, including an accidental First Four – picking the first four horses in exact order.

“I thought I had them boxed, but with the odds, I think it must have been in order,” he told the West Australian.

“There was no checking the form or anything. It was just a stab in the dark.”

Mr Baker, who bought a run-down pub two years ago after tiring of his career as a mechanic, said he planned to take his staff out for a lavish Christmas party and sink most of the funds back into the business.

Sportsbet described the punt as “absolute genius” in a media release, claiming it was one of the luckiest in Melbourne Cup history.