Thibaut Courtois' proposed return to Chelsea would be 'impossible' if the young goalkeeper had to vie for the No.1 jersey with incumbent Petr Cech, according to the father of the Belgium international.
Courtois is in his third successive season on loan with Atletico Madrid, where he has excelled, and has yet to make an appearance for Chelsea following his transfer from Genk during the summer window of 2011.
The 21-year-old's future remains unclear, with Atletico evidently keen to recruit him on a permanent deal, while there have been reports that Chelsea would strike a deal were they able to guarantee Diego Costa would leave the Vicente Calderon for Stamford Bridge.
Jose Mourinho, however, has moved to insist the Courtois remains part of the club's plans, even if Cech still remains the first-choice 'keeper. But, says Courtois Snr, Cech would have to leave Chelsea were his son to finally make a full-time move back to west London.
"Chelsea have a good goalkeeper in Cech, so cohabitation with both is not possible," he told RTBF.
"Alternating between the two is possible on paper but this is not what we want. This is not a situation we want.
"For now, we expect to discuss with Chelsea but it is impossible for Courtois to join a club to be their No.2 and the conclusion is the same for Petr Cech."