Zinedine Zidane's return to Real Madrid has pleased Iker Casillas, but Porto's goalkeeper believes that Los Blancos' hierarchy must realise they have made mistakes.
Zidane quit his role at Madrid in May 2018, following a third successive Champions League triumph, but made a sensational comeback to the club following Santiago Solari's sacking.
Madrid bounced back from their Champions League exit to Ajax by beating Celta Vigo 2-0 in Zidane's first game back in charge, but sit 12 points adrift of LaLiga leaders Barcelona.
And Zidane's former club-mate Casillas has urged Madrid to learn their lessons following a turbulent nine months in which both Solari and Julen Lopetegui – Zidane's initial replacement – both lost their jobs.
"It is clear that the hiring of Zidane makes me very happy," Casillas said, speaking at a 'LaLiga Icons' event.
"But also the hiring of Zidane, and before that Solari, means that things have not gone well before.
"The dismissal of Lopetegui, it was perhaps because the club did not understand that things are not going as well as they should go. When Solari entered, he had to improve or change the direction of the team again.
"Of course when Zidane comes it is a reason for joy for all the fans of Madrid for all that has been achieved in recent years, but also it is because something has not gone well."
Casillas spent his entire career with Madrid until leaving for Porto in 2015, winning five LaLiga titles and three Champions League trophies during his time at Santiago Bernabeu.
The 37-year-old's contract at Porto is set to expire at the end of the season, and though Casillas revelead that discussions have been held over extending his deal, he is open to playing in LaLiga once again, despite acknowledging that it is unlikely.
"I've been lucky enough to compete in LaLiga," Casillas said.
"Unfortunately I cannot be there now. It is a bit of everything, what has happened with the national team, what I did at Madrid, it's going to be very difficult to repeat those successes.
"The stage at Madrid is past, but I would love to return to LaLiga."