Barnsley are set to make at least £7m from the £47.5m transfer of defender John Stones from Everton to Manchester City.
The 22-year-old England international has become the most expensive defender ever signed by a British club – and the second priciest in the world – after signing a six-year deal with the Etihad club.
A sell-on clause means that Barnsley, who sold Stones to Everton in 2013, will get between £7m and £9m from the deal.
Stones, whose fee is the second highest paid for a defender after the £50m Paris St Germain paid Chelsea for David Luis, was named in City's official Champions League squad, published on the Uefa website, before the transfer was confirmed.
"It's an ambitious club with a great manager so I can't wait to get stuck in," he said.
"I know it will be tough getting a place in this team but I'm determined to become the best player I can be and help us to success."
In a short statement Everton confirmed they had received a "record fee" for Stones.