kick in the balls

noun1

1. •
   (slang, vulgar) A great setback or disappointment.

   • Jan 23 2009, Wokingham Times - Local Rugby Round-Up "Losing to Wallingford was a kick in the balls for us so we know we can't take any team lightly", said player/coach and lock Ben Hughes
   • April 16 2010, Scottish Daily Record - If you laugh at people for having a go on reality shows then you're an idiot, blasts Barry Hyde of The Futureheads "It's still a kick in the balls whether you've made the label drop you or they reject you."