Monaco led all clubs with €289 million profit in transfers this summer - study
The sale of Kylian Mbappe helped Monaco to a €289 million profit in the summer transfer window, the largest figure among clubs in Europe's top five leagues, according to a CIES Football Observatory study.
After winning Ligue 1 last season, Monaco unloaded a number of their stars, led by Mbappe's €180m move to rivals Paris Saint-Germain, though it was technically on an initial loan.
Also leaving the club were Benjamin Mendy (€57.5m) and Bernardo Silva (€50m), both to Manchester City, and the €40m Tiemoue Bakayoko to Chelsea.
CIES calculated that Monaco made €394m in transfer fees, while spending only €105m on replacements, led by the €30m acquisitiion of Keita Balde from Lazio.
That left them with the biggest profit in Europe, well ahead of Borussia Dortmund's €110m, which was sparked by the €147m sale of Ousmane Dembele to Barcelona.
Also making big profits were Lyon at €72m, Real Madrid at €47m, and Serie A clubs Fiorentina and Sampdoria at €42m.
Conversely, PSG paid the most, at €343m in the whole after spending €418m, and only selling off €75m. They were followed by AC Milan, whose new Chinese owners spent €250m to just €51m in sales for a €189m balance.
Manchester United were third on the list with a €186m negative balance, followed by Premier League rivals Manchester City (€173m) and Chelsea (€106m).
CIES found that 41 of the 98 clubs in top divisions in England, Spain, Germany, France and Italy made a profit. Of those leagues, only Spain's La Liga earned a positive balance at a modest €9m.
The Premier League shelled out the most at €835m -- six times more than the next league, Serie A, at €139m. Bundesliga clubs had a total combined deficit of €81m, while Ligue 1 teams were only down €55m despite PSG's big spending.
Using an algorithm to predict players' values, CIES also found that PSG and Barcelona overpaid for their new stars -- €87.4m more than expected in Mbappe's case and €51.2m too much for Dembele.
The biggest bargain against expected value was Liverpool's €50m signing of Mohammed Salah, who CIES valued at €19.4m more.
Sevilla's €10m signing of Man City's Manuel Nolito was €17.4m less than expected, while Chelsea's €39m Antonio Rudiger deal was €15.2m less.
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