Celtic manager Gordon Strachan believes £12million could not guarantee a like-for-like replacement for Neil Lennon.
The 35-year-old Northern Irishman decided this week that he will end his seven-year relationship with his boyhood heroes at the end of the season.
Since the former Leicester midfielder took his decision to quit there has been some debate as to the value of the player to the Celtic side.
But the Hoops boss said: 'If you gave me £12million I could not guarantee that I could bring in somebody with a winning mentality like that.
'I think for us to go out and find a 'new' Lennon will be impossible, so we just have to adjust with what we've got. Manchester United couldn't replace Roy Keane - they just changed the system.
'Michael Carrick isn't the same as Roy Keane but they keep trundling on. My conversation with Neil was very private but if he'd have wanted to talk about a contract we'd have talked.
'But he is really happy with himself since that decision was made and he is looking forward now.
'People will remember Neil Lennon as a great player, a great captain and a winner of back-to-back championships who walked away.
'That shows a bravery on his part and sticking around for so long shows you how mentally strong he is. If you have not appreciated him, you don't know the game. So why worry answering these people?'
Celtic defender Stephen McManus, tipped to take over the captaincy, admits he was not totally surprised by the Lennon news.
He said: 'A few of us have spoken to Lenny about it once or twice and so some of us expected it. He's been terrific for this club over the length of time he's been here and he'll be sadly missed on and off the pitch.
'All of the lads have nothing but praise for him, he's been absolutely superb. You learn from all of the experienced players, not just Lenny.
'You can't buy experience. It comes with age and the older lads that have been here, like Dion Dublin, Roy Keane and Paul Telfer, have been fantastic. So it will be a shame to see Lenny go.'
