Nigel Worthington made six changes to the side that drew at Derby on Saturday, with youngster Andrew Cave-Brown making his full debut and a bench full of Academy products. Cave-Brown's joy was short lived, however, as the Scotland under-19 international was stretchered off after half an hour.
McKenzie, seeking a move away from Carrow Road, was true to his word and turned in a committed performance despite being unsettled, opening the scoring from an Ian Henderson cross early in the second half.
City wrapped up the game with 25 minutes left, Henderson again involved as Dickson Etuhu netted his first goal in Canaries colours, tonight the new white away strip for the first time.
Norwich will learn their second round opponents when the draw is made on Saturday lunchtime.