St Ledger, who has been sidelined since suffering a hamstring injury at the start of October, played the first half as the development squad drew with Leeds on Monday afternoon.
However, Foxes boss Nigel Pearson insists the Republic of Ireland international centre-half still remains some way off a return to first-team football.
"He had half a game but he's got a long way to go," said Pearson. "It's good that he's training and got some pitch time but he's quite a long time out now so it's important that we get the balance right.
"I don't want people to start putting huge expectation on him getting back in the next week or so because that's not going to happen.
"But it's good to get him back amongst the players and training and he'll feel a lot better himself about getting some pitch time and that's always important in a player's rehabilitation."
Karlton Watson scored Leicester's goal in the 1-1 draw.