Town boss Mick McCarthy says former Blues striker Jack Marriott, now with Peterborough and the top scorer in League One, was “disgraceful” and unfit when he came back for pre-season in 2014, the summer prior to his final season at Portman Road.
Marriott, now 23, came through the Town academy having been signed as a schoolboy from Kettering.
He had hugely successful spells on loan at Woking in the Vanarama National League but was unable to replicate that success when out at clubs in the EFL or in his handful of appearances with the Blues.
After one League Cup start and two Championship games from the bench for Town without finding the net, the Beverley-born frontman was let go at the end of the 2014/15 campaign.
He immediately joined Luton with whom he scored 28 goals in two seasons before moving on to Posh last summer and having scored 32 times during 2017/18 (26 in League One) has been linked with Championship sides including Leeds, Hull, Cardiff and Aston Villa.
Asked whether he regretted letting Marriott move on, McCarthy said: "I wish the lad well and that decision was made by pretty much everybody.
"I take responsibility for it, but it was made by everybody. There was nobody saying we should keep him.
"I think he’s lost about a stone and a half since he was here. He came back that pre-season before we let him go and he was getting pretty much lapped by people.
"So I’d have to say he was disgraceful that pre-season, he wasn’t fit in any shape or form and I said to him when played them in pre-season when I knew he’d score, I said we’d have to score two because Jack would score, and he did.
"And I said to him after the game, I said, ‘So where’s that other fella that used to train with us, that little fat one?’. And he laughed at me and said, ‘All right gaffer, yeah, yeah, yeah’.
"I said, "Fair play to you, I’m delighted for you’. It doesn’t matter to me when they finally cop on, so however he’s done it, he has and he’s done brilliantly.
"He wasn’t going to do it here, he just wasn’t. He had to move, he’s had to grow up and congratulations to him, I’m thrilled for him.
"I say to them all when they leave here, ‘Go and play and have 200, 300, 400 or 500 games and come back and you can shake my hand and you’re my equal’. I love it for him, I’m delighted and good luck to him.”