Victory at the King Power Stadium would earn the Terriers an FA Cup fifth-round home tie against Wigan Athletic on Sunday.
Defeat, however, to the Foxes will mean Town travelling to Burnley in the Championship and caretaker manager Lillis is adamant the prospect of having three league points at stake this weekend is at the forefront of his mind.
He said: “There might be a few of the young lads who get a chance (at Leicester). We have got to look at the bigger picture of the Burnley game.
“I learned quite quickly at Derby when I went with the same starting XI as had played against Crystal Palace just a few days earlier.
“There were a lot of tired bodies after getting a win and a draw in our previous games (and Town lost 3-0).
“So, I will sit down and look at the Leicester and Burnley games to send out teams that we think can get results. The bread and butter is the Championship.
“Getting a Premier League team would be great, but we have to get the selection right.”
Lillis is not helped by a growing list of absentees with neither Neil Danns nor Jermaine Beckford able to play against their parent club even before the latter suffered a hamstring tear.
Captain Peter Clarke is also out along with Lee Novak, because of injury, while James Vaughan is a doubt with a broken tooth leaving youngsters Jordan Sinnott, Chris Atkinson, Matt Crooks and Under-18 midfielder Duane Holmes hoping for a chance.
Last six games: Leicester City WWWDWL, Huddersfield Town DLDWLD.
Last time: Leicester City 6 Huddersfield Town 1; January 1, 2013; Championship.
Referee: James Adcock (Nottinghamshire).