Michael Laudrup's dismissal as manager of Swansea City in February 2014 was due a conflict of interest with his agent taking a cut from transfers, according to El Mundo.
The newspaper reports that that Laudrup's agent Bayram Tutumlu pocketed €4.3 million (£3.6m, $4.6m) from seven signings made through him by Swansea between 2012 and 2014.
Tutumlu charged a high commission percentage, to be paid from the total agent fees, when players that Laudrup requested were signed by the South Wales club.
El Mundo, using information taken from an article published on Danish newspaper Politiken, one of their partners, claims that Tutumlu agreed a contract with an unnamed Spanish agency and earned €1.