Arsenal winger Ryan Smith has joined Leicester on loan until the end of the year and goes straight into the squad for Saturday's game with Derby.
The 18-year-old is one of the most highly-rated wingers in the country, and his loan could be extended to the end of the season.
"He's a player with bags of potential. I'm sure he will excite the fans," boss Craig Levein told the club website.
The terms of Smith's loan do not allow him to play in the Carling Cup.