Scott McDonald left Celtic shortly before Neil Lennon was handed the managerial reins, initially on an interim basis and then on a permanent contract.
The Australia international was a key part of the Parkhead set-up, though, during Lennon’s spell as first-team coach.
He has therefore seen enough of the former Northern Ireland international to know what he is all about.
McDonald is aware of how badly Lennon hates to lose, something he did not do a lot of during a successful spell at the helm in Glasgow.
He has taken something of a gamble in accepting a first coaching post in England at Bolton Wanderers, but has already made quite an impact on the Macron Stadium squad.
He told Sky Sports: “Knowing Neil, he’ll want his players right at it. He’s a winner.
“Where they were, to where they are now, I think he’s had a massive reaction there and will do a great job there over time.
“We’ll probably have to take it to Bolton a little bit and hopefully we get the three points.”
Millwall and Bolton sit level on points at present, with 23 collected from 21 fixtures.
Both are looking anxiously over their shoulder, though, with only five points separating them from the relegation zone.
It is the Trotters who have shown the greater signs of life over recent weeks, with Lennon overseeing a six-match unbeaten run.