Blues left-back Evan Horwood, who played with Naughton at Sheffield United, recommended him to then manager John Ward after impressing during a loan spell at Gretna - coincidentally replacing Carlisle-bound Horwood.
But Naughton's promotion to the Blades first team thwarted Carlisle's move for a player who is now on the cusp of an £5 million move to Everton, Aston Villa or Tottenham Hotspur.
Manager Greg Abbott, who at the time was assistant manager, told the News & Star: "We actually asked Sheffield United if we could buy him, which shows the work we are always doing behind the scenes in identifying good, young players.
"We knew Kyle had done well at Gretna and we made enquiries about him this time last year.
"Evan had recommended him to us and we tried to get him before the start of last season, but he then got into the Sheffield United team."