Jose Mourinho says Claudio Ranieri has been punished for his success and feels Leicester City should rename their stadium in his honour.
Ranieri was sacked on Thursday, less than 10 months after guiding Leicester to a stunning Premier League title triumph, with the club's board expressing their concern at the possibility of relegation from the top flight.
Mourinho posted a picture on Instagram following the news to express his support for Ranieri, in which he encouraged the 65-year-old to "keep smiling".
And the Manchester United boss has continued his defence of the Italian, claiming that his own departure from then-champions Chelsea in December 2015 was "peanuts" compared to Leicester's decision.
Speaking at a news conference on Friday, in which he wore a polo shirt emblazoned with Ranieri's initials, Mourinho said: "My words are my shirt, with his name. It's my little homage to somebody that wrote the most beautiful history of the Premier League, who probably deserves the Leicester stadium to be named Claudio Ranieri.
"They made history two years in a row: one year because they did the most beautiful thing in the Premier League, and now with the decision that I think has everyone in football united but it's very, very difficult to accept.
"But it's good for all of us to realise how football is and we need to adapt to it. I thought, last season, when I was sacked as a champion it was a giant negative thing. Now I realise it was peanuts compared to Claudio."
Widespread reports in England have suggested that senior Leicester players demanded that the board sack Ranieri, although interim boss Craig Shakespeare has denied that the dressing room turned against him.
"Nobody can delete what he did. If some of the stories I'm reading are true, or have just a little bit of truth, it's difficult to find words to justify that," Mourinho said.
"I'm not inside, I have no right to try to find scenarios. I think it's Claudio's fault. Last season, if they finished 12th, it would be amazing and he'd still be in a job. So it's his fault. He's paying for his success.
"Probably the season started with the typical selfishness of others, thinking about new contracts, leaving, more money, forgetting about who helped them reach a certain level. But this is not just football, it's our world. Some principles are going away a little bit.
"I lived a similar experience but I repeat, it's peanuts compared to Claudio's. But nobody can delete the history."
United have been drawn against Rostov in the last 16 of the Europa League, with the away leg in Russia set to take place just four days before the FA Cup quarter-final against Chelsea at Stamford Bridge.
Mourinho, who had feared a lengthy away trip before Friday's draw took place, feels United have been handed as difficult a task as they could have expected.
"It's a bad draw in every aspect," he said. "It's far and it's difficult. It comes in a bad period for us and they are a very difficult team.
"They had a very good Champions League campaign, they beat Ajax and Anderlecht in the play-offs and they managed important results against Bayern Munich and Atletico Madrid.
"I know the manager well, I played against him when I was at Inter. The team is very defensive, very physical. But after Southampton and Bournemouth, we focus on it and we go for it."