Former Celtic kid Cameron Harper has claimed the Hoops lacked solid team spirit amid 'cliques' and a lack of 'togetherness' in both the first team and youth set ups.
The 19-year-old winger departed for New York Red Bulls in March despite the Hoops being keen to strike a deal to keep him in the Scottish Premiership.
The American made one first-team appearance for the Hoops under Neil Lennon, which came in January this year in a 1-1 draw against Hibs.
And he insists life is good under Austrian coach Gerhard Struber in the Big Apple - and the behind the scenes cohesion between players a far cry form his experiences in Glasgow.
He told American Soccer Now : “From what I've seen from the team so far - they are very, very good and I don't see why we can't go pretty far.
“Definitely, there's a good spirit. I think that's one thing at Celtic that sometimes did lack, in terms of our reserves or our first team - there were kind of cliques and there wasn't a full togetherness.
"At Red Bull, everyone wants to work hard for one another. He's creating a real togetherness and a real spirit where, if you're not going to give 100%, don't even bother showing up type of thing.”
The Hoops were keen to keep the starlet but failed contract negotiations meant the creative star was put into cold storage before his unlikely first team bow was brought about due significant upheaval that followed the Dubai trip.
He said: “The contract talks started happening, there was no kind of agreement on anything.
“When they shipped me back down to the reserves, that's when I got it tough because there's only a few guys there. There are about 5-10 guys there per day and people were out on loan. I would say maybe in September, it was getting pretty bad in terms of my place there. But I was still playing games, so it was okay.
"Leading up towards December, January, when I had a good idea about leaving, that's when it kind of got a little bit uncomfortable.”
And yet, the Yank is keen to focus on the positives from his time in Scotland.
He admited: “When I went there, I was 16, playing in the Development Academy in California.
“It wasn't even an MLS team – so, it wasn't too serious. Then to go from that straight to an environment where even at a Under-18 level or Under-23 we needed to win every game - it helped you become more serious.
"I realised I have to take my development very seriously if I really want to improve. That winning mentality, sometimes people can say: 'oh, it's about development over winning.' And I agree - but when you need to win every game, that's when you also develop because you can't just take games off.”
“Getting used to an environment where it's pretty cutthroat, is definitely going to help in terms of coming to a first team environment at Red Bull which is also very cutthroat.
"Only the best 11 guys get on the field - so you want to be one of them.”
