Christiansen, 44, was sacked on Sunday after overseeing a run of seven matches without a victory, with Paul Heckingbottom lured from Barnsley as his successor.

Radrizzani told the Yorkshire Evening Post: "Anything that doesn't work is a mistake so yes, I did make a mistake.

"I apologise to the fans and the club, and for my experience I need to learn and analyse better my choice before making it.

"We need to share this responsibility but probably the job was a little bit too big for him at this point in his career.''

Christiansen, the former Barcelona and Spain striker who grew up in Denmark, managed in Cyprus before Leeds appointed him last summer.

Leeds topped the Championship in early September, but their winless run of six matches has left them 10th, and they were knocked out the FA Cup last month by League Two side Newport in what Radrizzani has labelled a "shame game.''

The Italian admits he was "really keen to change'' the head coach at the beginning of January.

He said: "If you watch the games we conceded so many chances early on, in the first few minutes. This is a sign that mentally the players are not relaxed.

"They are stressed and this is why I could feel that probably the manager was not transmitting security and confidence.

"I waited for a long time before taking the decision and gave him many chances. Already at the beginning of January I was really keen to change.

"Victor [Orta, Leeds director of football] convinced me to hold on and give him one more, one more, one more ... extra chances but at the end, something was missing.''

Radrizzani said Christiansen "probably lacked a little bit in terms of knowledge of the football'' and added: "He needs to improve in terms of communication and leadership and confidence, which is a word I used a lot with him but it didn't improve.

"I had two situations that put me in the mind to change. First, the crazy Christmas period where we had four games in eight days. I was expecting [Christiansen] to manage the group in terms of changing some players. At the end, what happened was the opposite.

"As a result we had to change 10 players and have a shame game against Newport. Congratulations to them but we didn't come onto the pitch to play. That was a message to consider a change.''

Heckingbottom oversaw Barnsley's promotion to the second tier in 2016, guided them to a 14th-placed finish last term and left with them sitting 21st in the table.

Regarding the 40-year-old, Radrizanni said: "We want to have on board someone with a bright future but at the same time a knowledge of the territory.

"He's someone who could lead the group and that's what we need now. We need a leader.

"In the long run I think we could hopefully have found a good manager. Time will show.''