Olesia, who works at a horse stable, was thrilled to discover that she had won a cool £240,000 on William Hill's Leprechaun Luck Game.
The Suffolk lass has since quit her £290-a-week job and will spend the cash on her wedding to ex-jockey boyfriend, William Rovetti, and visiting family in Ukraine.
The 29-year-old told The Sun that she was "shouting and jumping and screaming like crazy" and that the money has "completely changed her life".
Despite the win, the stable girl still can't believe her luck: "I wake in the morning and think it is a dream, then realise it is real," she said.
William Hill's Jem Maidment said "We are thrilled for Olesia."
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