Graeme Souness says Celtic would be "crazy" to not offer Neil Lennon a contract as permanent manager after leading them to an eighth straight league title.
Lennon signed a deal as interim manager in February until the end of the season after Brendan Rodgers left to join Leicester.
Celtic wrapped up the Scottish Premiership title under Lennon with a 3-0 win at Aberdeen to add to their League Cup success this season.
Since Lennon's return to the club Celtic are undefeated and could win a third domestic treble in a row with a win over Hearts in the Scottish Cup final on May 25.
Sky Sports' Graeme Souness says the champions would be making a mistake not to extend Lennon's deal, who won the title three times in his previous spell as Celtic manager.
"I worked with Neil Lennon for two years in television and he's as good as anyone I've worked with," said Souness.
"He gets his thinking from Martin O'Neill who got his from Brian Clough.
"Neil Lennon knows his stuff. I hope they don't employ him as a Rangers supporter. But I want him to keep the job as he's a good guy. They'd be crazy to get rid of him.
"If Neil wins the treble how much better can it get? He has fulfilled what he could do."