Speaking to the club website, Kennedy said: "I remember Stephen being at one of my soccer schools and he really stood out as being a brilliant prospect. I got on the phone to Steve Heighway and Roy Evans and said you have got to take a look at this boy."
Kennedy praised Warnock's performance yesterday, and said he believes the player has a great future at the club.
"I thought he was fantastic against Leverkusen. I really like him as a left back. He has a great left foot and can pass the ball and get forward. The tackle he made near the end was just brilliant and Rafa will like that seeing a player never giving up and showing great commitment," Kennedy said.
He added: "I hope Stephen can push on now and get a good run of games because he deserves to."