After he was overlooked in Wednesday's pre-season and rookie drafts, Jolly, 32, slammed Buckley for how he handled his delisting after four years at the Westpac Centre.
The two-time premiership ruckman has a history of lashing out at ex-coaches, after he also denigrated former Melbourne boss Neale Daniher, with Jolly claiming he was 'intimidating' and 'hard to approach' in a newspaper column last year.
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This time around, Jolly slammed Buckley in an interview with The Age, claiming the coach 'found it a lot harder accepting that I had opinions about things' and that the excuses given for his delisting 'were all bullshit'.
Buckley, speaking to SEN, was empathetic of Jolly's predicament, but was also disappointed with the comments of the 237-gamer.
"It's probably the toughest time of a career when you're sort of coming down the other side and it can be a really difficult period to manage," Buckley said
"Darren's been a fantastic player for this club for four years, a premiership player in his first year in 2010, a dual premiership player... he'll be feted in time. But right now he's obviously disappointed he hasn't been able to continue that career
"He's still coming to grips with his footy mortality. We just need to be sensitive of that. And understand when people are hurt and haven't got what they want, sometimes things come out."
McGuire also credited Jolly's claims to his disappointment at being overlooked in yesterday's drafts.
"I'm very disappointed. It's just unfortunate language, it's as simple as that," McGuire said on his Triple M morning show.
"People get to the end of their career. Darren has been a magnificent player for the Collingwood Football Club.
"His performance in 2010 to help the club win the premiership was fantastic. He had a great finish to his career at our club, a lot of people spent a lot of time helping and supporting him.
"He has got to the end of his career - unfortunately yesterday, 18 teams passed on him.
"The warrior within sometimes spills out, and I think that's unfortunate because that leaves a bit of a... nasty taste."
McGuire also backed in Buckley, who has come in for criticism in his two years at the Magpies' helm for poor relationships with his players.
"That is the most inappropriate word for Nathan Buckley that you could ever use," said McGuire, of Jolly's claim Buckley was a coward.