Norwich led with two early first-half goals before the home side drew level before the break. The Canaries then appeared to have the game all sewn up, taking a 5-2 lead before Leicester hit back and stunned the Canaries with three goals in the final 10 minutes.
Darren Bloodworth took charge of the team as City made the perfect start, opening their account in less than 60 seconds when Korey Smith did well to create an opening for Luke Daley to find the net.
After 16 minutes City extended their lead when Daley raced clear of the defence to fire the ball home.
Daley then turned provider when he sent in an inviting cross that Jordan Yong just failed to connect.
After 24 minutes Leicester reduced the arrears when, from a free kick, the ball came back off the woodwork and fell kindly for Billy McKay to stab the ball home.
Four minutes later the home side were back on level terms when they were awarded a penalty. McKay stepped up to fire the ball past Declan Rudd.
Norwich might have regained the advantage before the break but Damon Lathrope saw his curling shot go just wide of the target.
Into the second half and Rudd did well to save from Craig King before City scored their third with a well-placed shot from Smith and then three minutes later they extended their lead when a long clearance from Rudd found Daley who rounded the keeper to slot home his third of the game.
Bloodworth introduced trialist Jordan Dowdican who marked his first Academy start with a goal on 75 minutes to fire City into a 5-2 lead.
It appeared that the Canaries had all three points in the bag but Leicester, and in particular McKay, had other ideas as they pulled a goal back with their second penalty of the game three minutes from time.
McKay scored his fourth and amazingly in injury-time McKay scored his and Leicester's fifth when Rudd turned a header on to the crossbar, the ball then being bundled over the line by the Leicester front man.
City Line-Up: Rudd, Adeyemi (Cooper 63), O'Toole, Lathrope, Habergham, Miller, R Kelly, Smith, D Kelly (Dowdican 60), Daley (Dawkin 77), Yong.
Top Canary: Tom Miller.
