The Buckland youngster was shown the door in the summer of 2011 and handed a free transfer.
Cotterill had actually granted the midfielder both his two Blues appearances, before sending him on loan to League Two Cheltenham for the 2010-11 season.
Pack was released upon his Fratton Park return, yet was reunited with Whaddon Road on a permanent deal.
Now aged 29, he’s in his fifth season in the Championship with his Cardiff team lying seventh, kept out of the play-offs by goal difference.
Cotterill told The News: ‘I told Marlon that he needed to go and play regular league football.
‘If you spoke to him today, he would tell you the same thing.
‘Probably at the time for Marlon, there was competition in there. We had a few that could play central midfield.
‘Marlon has grown into what I would call a first-class professional, but back then he was a young boy who had been on loan at Dagenham.
‘He asked me what I suggested and I questioned if his agent had anything lined up. Well, I knew Mark Yates at Cheltenham, he had played for me, so I mentioned it to him.
‘We offered to help with wages, not that Marlon’s wages were a problem for us anyway, and he joined them on loan.
‘I remember one of Cheltenham’s board members phoning me up after about six weeks and cheekily saying “What have you sent us here?”.
‘I replied “You what?”. He said: “It’s Marlon. It doesn't like he’s going to get into the team”.
‘I answered: “Give him a chance, he’s only been there six weeks. I’ll tell you what, make sure you call me back when he gets into the team and plays really well for you, because that’s what he’ll do”.
‘I remember hanging the phone up and being really disappointed, even though he said he was only joking.
‘I knew Marlon would do a good job at Cheltenham and get to play 30-40 games, which is what I felt he needed. It ended up being a great move for him and he then went back permanently.’
Cotterill would come across Pack once more, this time at Bristol City.
With Cotterill appointed boss in December 2013, the midfielder eventually became a pivotal performer.
In 2014-15, the Robins claimed the double of the League One title and the EFL Trophy during a remarkable campaign.
Cotterill added: ‘I went in there and remember saying to Marlon to not have any fears about what was going to happen moving forward.
‘I had seen him enough and how he had performed at Cheltenham. He had grown into a really good professional and still is to this day,
‘I see him quite often and get on great with him. The two years I worked with him at Bristol City he was fantastic.’
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