The Saints were thumped 3-0 at West Brom in their last outing, although they may have been eyeing this fixture.
Meanwhile, Brendan Rodgers will be hoping that Kelechi Iheanacho can continue his excellent scoring form to fire the Foxes into the FA Cup final.
Iheanacho has nine goals in his last five matches, including a double against West Ham during Leicester’s 3-2 defeat to the Hammers last time out.
Here’s everything you need to know about the match:
When is it?
The fixture will kick-off at 6.30pm GMT at Wembley Stadium.
How can I watch it?
The match is live on BT Sport 1 with coverage starting from 6pm GMT.
What is the team news?
James Maddison, Ayoze Perez and Hamza Choudhury are all available after being dropped for breaching Covid restrictions last week. Caglar Soyuncu and Cengiz Under are also back in the squad, but Wes Morgan (back), James Justin and Harvey Barnes (both knee) remain out.
Michael Obafemi is back in training after a muscle issue that has kept him out since January, but on-loan forward Takumi Minamino is cup-tied after appearing in the competition for Liverpool. Oriol Romeu (ankle) and William Smallbone (knee) are out.
Leicester XI: Schmeichel; Söyüncü, Evans, Fofana; Castagne, Ndidi, Tielemans, Perez, Ricardo; Vardy, Iheanacho.
Southampton XI: Forster; Walker-Peters, Bednarek, Vestergaard, Bertrand: Armstrong, Diallo, Ward-Prowse, Djenepo; Ings, Redmond
Anything can happen, especially in the FA Cup, but it is difficult to look past Leicester for this clash. Iheanacho is in free-scoring form and he will fire the Foxes to the final. 3-1 Leicester.