This could be one of the worst winners so far this year. After raising the trophy he went and crush out in the next tournament. Haven't heard this from men's side though. Womens? it happen a lot as far as I know.
Happens quite often on ATP as well. Alex de Minaur has won Atalanta 2 weeks ago and then lost in first rounds of next 2 tournaments. His opponents weren't anything special as well. He lost against Goyowcyik in Washington and against Evans here in Montreal, if I remember correctly. Cost me some money.