Chelsea face paying Brighton and Hove Albion several million pounds for two academy players who switched to the London club in July 2022.
A football tribunal is understood to have set an initial or basic fee plus add-ons for Shumaira Mheuka, 16, and fellow Londoner Zak Sturge, 19, according to Football Insider.
The football news website said that the Professional Football Compensation Committee reached its decision after meeting on Tuesday 20 February.
Mheuka, known as Shim, was just 14 when he left for Stamford Bridge after five years with the Albion academy. The footballing prodigy had already made his Under-18s debut for the Seagulls.
Football Insider said: “Brighton will receive a record fee for a 14-year-old after a tribunal ruled that Chelsea must pay up to £4.25 million for Shumaira Mheuka.”
The Blues are expected to pay an initial £1 million for the prolific young striker, with £250,000 due upon his signing a professional contract.
The wealthy west London side will owe another £250,000 if and when Mheuka makes his professional Chelsea debut and another £250,000 if the England Under-17 international makes his full international debut.
More stage payments fall due up to a further £2.5 million depending on a number of other conditions including cumulative first-team appearances.
Football Insider said that Mheuka would have to play in at least 100 matches and receive a full England call-up for the full £4.25 million to fall due.
In addition, a sell-on clause will entitle Brighton to be between 20 per cent and 25 per cent of any future transfer fee.
The basic fee for Sturge was set at £900,000 but could reach £3.4 million with add-ons, plus Albion are understood to be entitled to 20 per cent of any future transfer fee.
The add-ons include £150,000 if the left back makes his Chelsea debut, £250,000 if he plays for England and up to £2.1 million if the young defender makes 100 first-team appearances.
Sturge went out on loan to League One promotion contenders Peterborough at the start of the season but was recalled last month.
Last week, Chelsea poached Brighton’s head of recruitment, Sam Jewell, having previously signed his predecessor Paul Winstanley as part of a swoop that started in September 2022 with Graham Potter’s move.
The Londoners have now signed 11 players or other staff since Todd Boehly and Clearlake Capital bought the club that summer.
Potter took several key backroom colleagues including assistant manager Billy Reid, coach Bjorn Hamberg and recruitment analyst Kyle Macaulay.
Bruno Saltor and Ben Roberts joined Potter at Chelsea while three players – Moises Caicedo, Marc Cucurella and Robert Sanchez – earned Brighton about £200 million.
Ecuador midfielder Caicedo, 22, was sold for a British transfer fee record, reported to be £115 million, including performance-related add-ons.
Brighton are currently seventh in the Premier League on 39 points while Chelsea are four places behind in 11th place with 35 points and a game in hand.