Neil Lennon risked being "finished" as a manager if he had failed to lead Celtic to a ninth successive title, says former boss Gordon Strachan.
And Strachan believes the 48-year-old has "reinvented himself" after his ill-fated spell at Bolton Wanderers.
Lennon completed Celtic's treble treble after replacing Brendan Rodgers in February 2019, and last term added the record-equalling title and League Cup.
"When he first came back it wasn't unanimous," said Strachan.
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"There were a lot of doubters. He would also have been thinking, 'If I take this job and fail, that's me finished.'
"He then had to deal with this problem of 'Am I going to lose nine in a row?' It was an edgy time at new year. He's dusted himself down with his players and come back and blown the opposition away.
"So that shows he has mental strength, intelligence, he can deal with anything."
Lennon spent two seasons as Celtic captain under Strachan before joining his coaching staff in 2008 and taking charge two years later.
The Northern Irishman was at the helm for the first three titles of Celtic's nine-in-a-row run, then had spells at Bolton and Hibernian before returning following Rodgers' abrupt departure for Leicester City.
Speaking on BBC Scotland Sportsound, former Scotland manager Strachan added: "The fact he's left Celtic and went, 'Oops, what have I done?' He's had to deal with that, go to Bolton. And I know when you go to teams like Bolton after being at Celtic, you just don't get the mentality.
"Then he went to Hibs and has come away with formations that suited the players he had. It was fantastic what he did there.
"He's reinvented himself as a manager. And that period at Hibs allowed him to express himself more freely."
Lennon has been named manager of the year for the third time by the Scottish Football Writers' Association after his side - who held a 13-point lead with eight games left - were crowned champions of the curtailed Premiership.
Strachan believes he is a "worthy" recipient.
He said: "He's come back to Celtic and said, 'Well done, Brendan, that's fantastic. But I need to watch football that I really want to watch.'
"Neil had to do his own thing, and tweak what Brendan was doing without anyone really noticing.
"Neil and Celtic are made for each other. It's only right he gets it [manager of the year], for a multitude of reasons."