However, the manager was at pains to explain Ledley was not being punished for a Hampden performance which fell below his normal consistent standard.
"Joe wasn't dropped," insisted Lennon, almost annoyed at the very notion.
"We just wanted to have Kris Commons in from the start because we were at home and felt we needed another goal threat. I know what Joe can do, and he came off the bench to score a wonderful goal. That will do him the world of good."
Ledley can expect to be back in his starting place on Sunday when Celtic head to Fife to face Raith Rovers in the Scottish Cup. Lennon intends to show the First Division side full respect, though this is not a reaction to the disappointment of losing to St Mirren.
"I will approach this cup tie like I do every other game – we want to win it," he said, in a tone which indicated he will not accept crashing out of another competition.
Georgios Samaras and Emilio Izaguirre could be missing after picking up injuries in the win over Kilmarnock.
But Lennon is pleased to report that among those vying for a place in the side he will send out on Sunday is James Forrest, who last played on Boxing Day before another hamstring injury returned him to the treatment room.
His rehab has been carefully managed, with Juventus very much in mind, and Lennon said: "James is back in training and we are hoping to have him in the squad for this weekend because he has looked good. But we don't want to rush him, either."
Lennon is hoping to have keeper Fraser Forster – omitted from Roy Hodgson's Engand's squad to face Brazil next week – back alongside Tom Rogic.