The Foxes are in action for the fourth time in 12 days on Friday evening, winning all three of those previous matches, including a 1-0 FA Cup semi-final victory over the Saints.
City have just two confirmed absentees for their latest match, with James Justin and Harvey Barnes ruled out with knee injuries.
Veteran centre-back Wes Morgan is a major doubt, though he was never likely to get the nod over Jonny Evans, Wesley Fofana or Caglar Soyuncu in the backline.
There could be a change at left wing-back, though, where teenager Luke Thomas has been entrusted for the past couple of games.
Ricardo Pereira is back available and may get the nod in one of the wing-back slots, while Ayoze Perez is another of those pushing for a recall.
Perez netted in Leicester's 9-0 win at St Mary's on their last visit and has scored more Premier League goals against Southampton than he has against any other side (seven).
Jamie Vardy and Kelechi Iheanacho seem certain to get the nod up top, the latter having scored 14 goals in as many matches since the start of February.
Leicester possible starting lineup: Schmeichel; Fofana, Evans, Soyuncu; Pereira, Ndidi, Tielemans, Castagne; Maddison; Vardy, Iheanacho
> Click here to see how Southampton could line up for this contest
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