Darts player Gerwyn Price has won a planning battle with neighbours over his "boozy" late night practice sessions in his back garden.
Price, 34, has been allowed to finish work on the purpose-built practice room in an out-house at his home.
But neighbours were furious about his pals peeing over their garden wall during practice sessions.
Price is ranked number three in the world and has won almost £800,000 of prize money in the past two years.
But after buying the £84,000 home in Markham, Blackwood, in 2018, neighbours complained that his building works had caused £5,000 of damage to a retaining wall.
Jeffrey Smith, 59, said his 89-year-old mother Mary has also had to put up with "late night drinking and people urinating over the wall" since Price moved in.
Mr Smith told a planning meeting: "When they started building this structure I told him to stop and he just ploughed on.
“The retaining wall was straight but it is now going in different directions.
“My mother is absolutely heartbroken. She has lived here all of these years and she has never had any problems.
"Since this has happened I have had to endure my mother crying on a weekly basis."
Electrician Mr Smith says Price's garden "man-cave" is being built on the footings of his mother's wall - and has damaged it.
Speaking after the meeting, he said: "All this could have been avoided if he had built it a foot further away.
"It's not a practice room it is a man-cave where he goes with his mates to get drunk and celebrate winning a game of darts.
"They're up there until the early hours of the morning.
"My mother doesn't sleep too well and this one night she's looked out and there's these two mates peeing over her wall in her garden.
"My mother is a church-going woman and was a nurse for 57 years. She does not want to see that.
"She has been left in tears and sobbing by all of this."
But Price - who reached the semi-finals of this year's PDC World Darts Championship - dismissed the claims as "garbage" and promised to replace the retaining wall.
He told council officials: "This whole debate is not about the outhouse, it is about the wall which I said I would replace.
"As for the issues about noise, it is not true. I use this for my livelihood as a practice room.
"I am just somebody with a family who tries to do my best and some people try to drag me down.”
Caerphilly County Borough Council approved the plans at a meeting allowing Price to finish the works and erect a 1.8metre high fence in his garden.
Mr Smith said that for him, the matter is not finished.
He added: "I told him after the meeting, you may have won the battle but I will win the war."
"It could be resolved if he (Price) would pay for my mother's cost for the wall to be repaired and would get skips to remove the mess and rubbish he's made."
