Former Real Madrid president Ramon Calderon has cast doubt on Jose Mourinho's future at the Bernabeu, claiming the manager's recent controversies have been "harmful" to the club.
Mourinho saw his side crash out of the Champions League to bitter rivals Barcelona from the comfort of his hotel room, after being banned from the touchline.
The former Chelsea boss, who was sent to the stands during the first leg, made a string of claims in the wake of the 2-0 defeat last week, notably that Barca had been on the receiving end of favourable treatment from UEFA.
His mood will unlikely have been improved by the controversial decision to disallow a goal from Gonzalo Higuain when the score in the second leg was 0-0. Cristiano Ronaldo and Xabi Alonso have backed up their manager, claiming their exit from the Champions League was on account of decision making from the officials.
But it is the manager who has come in for criticism from Calderon, who feels Mourinho would have been better served congratulating Barcelona.
"I think what he did in terms of talking about UEFA and referees is not acceptable at all," Calderon told Radio Five Live. "It doesn't match with Real Madrid's history.
"I assume that he's a very, very good manager, but talking like that has been harmful for Real Madrid.
"I think big clubs can never blame the referee for their defeats. I think the semi-final was over in the first match at the Bernabeu when we lost 2-0.
"We invested €450 million in the last two years to build a very important and strong team, so if you lose you can't blame injuries, bad luck, the referee... If you lose, you have to congratulate your rival."
Barca are likely to clinch the Spanish title in the coming weeks and Calderon is unsure of Mourinho's position at the Bernabeu.
"It is difficult to succeed here because people are very demanding," he said. "There's a lot of pressure here. He said he's going to [continue] in his position next year, but you never know."