Popular but didn't rate - Stuart Armstrong. One of THE most overhyped players ever to pull on the Hoops imo. Had high hopes for this guy but the return we got from him in over 3 years at the club was a good 6 month spell under BR, the rest of the time he flitted between being pretty poor and bang average at best. To this day I still can't understand this guy's popularity amongst the Celtic support.
A special mention to Efe Ambrose. Popular because he was a really nice likeable guy but fuck me watching him play felt like being forced to watch a hyperactive wean on a 6 can Red Bull high running about a minefield with a pair of razor sharp scissors in each hand. A truly terrifying sight that had disaster written all over it made all the more worse because he WAS such a likeable guy you wanted to see succeed. Seeing him fail was like watching puppies being fed into a wood chipper!
Wasn't rated but liked - Erik Sviatchenko. To be fair he was rated by some but not by all. A solid enough CB, a key member of the Invincibles and out of all the CB's we had at the time I thought he was the most competent of the lot. I couldn't work out why BR dropped him then punted him as he hadn't let us down in any major way, we were light on CB's at the time and the only other CB's we did have were Boyata and Jozo, one prone to bouts of brain flatulence and the other who legend has it could get injured just by the mere act of looking at a football.