The midfielder missed Saturday’s win against Fulham due to suspension, and now misses the trip to the King Power with a hamstring injury.
The Chelsea manager made a host of changes for the game at Fulham, with Kurt Zouma, Reece James, Kai Havertz and Timo Werner all left out of the starting XI. James and Havertz return here, but Zouma and Werner remain benched.
Lampard is hoping victory at the weekend represents a turnaround for his side after an alarming slump in December.
But he acknowledges Leicester is a major test for his players against a side who are in the title race.
He said: "Leicester are a quality team, but we are not the only team in that position. Parts of the team are not firing and it is hard to win games in this league.
"But the work ethic is just as important as the confidence. The potential is there, it just needs to be unlocked.
“They're in it (the title race). We managed to get above them at the back end (last season), but it was a big ask. They are a good team, good players and a really good coach in Brendan.
"We have to consider ourselves as can we get a result against a competitor.”
Chelsea XI: Mendy, James, Thiago Silva, Rudiger, Chilwell, Havertz, Kovacic, Mount, Hudson-Odoi, Abraham, Pulisic
Subs: Arrizabalaga, Christensen, Jorginho, Werner, Zouma, Ziyech, Gilmour, Azpilicueta, Emerson Palmieri
Injury list: Kante (hamstring)