The Republic of Ireland international played over an hour for City while he continued his recovery from a knee injury that has kept him out of first team action since August.
Canaries ‘keeper Remi Matthews made a spectacular save to deny Michael Cain from the 12 yards ten minutes into the second half as the Foxes looked like running riot in Norfolk.
However after a string of missed chances, an equally spectacular solo effort from striker Jamar Loza with 20 minutes left secured the three points for the Canaries and left City with nothing to show for what was an excellent display.
Afterwards, Development Coach Steve Beaglehole told LCFC.com: “I can only say it how it is, and that’s that we were very unlucky not to have come away with the win let alone a point.
“That’s the best we have played all season for me, and yet we’ve been beaten, it’s quite hard to understand. We had a penalty saved and Joe Dodoo headed a good chance wide near the end, which is frustrating but it’s just one of those things
“St. Ledger played 65 minutes for us today and I have to say he was magnificent – he didn’t put a foot wrong - he’s a real credit to the Club.
“The young lads and the coaches have come to me and said what a great role model he has been for the squad. Having him with us was worth ten coaching sessions to my players without any doubt.”
After a quiet opening City had the better of the first half chances as Harry Panayiotou, Jak McCourt and Dodoo all went close, but couldn’t get their efforts on target, much to the relief over Canaries ‘keeper Matthews.
It was a similar story after the break as Cain almost capped off some incisive play with a 20 yard effort only to see it drift wide, while last season’s FA Youth Cup winning captain, Cameron McGeehan picked out Norwich’s Loza in space, but the striker couldn’t apply the finish.
Then on 54 minutes, City left back Callum Elder was brought crashing down in the box by Jacob Murphy, but Matthews was equal to Cain’s powerfully struck spot kick to keep the scores level at 0-0.
That was all to change in the 68th minute though as Loza latched onto a nice ball to charge down on goal, and despite being forced wide by Alie Sesay, was able to keep his balance and put an excellent finish beyond the reach of Adam Smith to claim victory for the hosts.
Norwich: Matthews, McNeil, Ayala, Gafaiti, Toffolo, McGeehan (c), Fox, Jacob Murphy, Loza, Hall-Johnson, Morris
Subs not used: Barker, Oxborough, McFadden, Hodd, King
City: Smith, Watson, Elder, McCourt (Nkumu 81), Sesay (c), St. Ledger (Frempah 65), Cain, Paratore, Panayiotou, Dodoo, Daniels (Stankevicius 71)
Subs not used: Sharpe, Anton