Head coach Tonda Eckert takes his play-off chasing charges to the relegation-threatened Foxes at King Power Stadium for a 7:45pm kick-off.
Normally, supporters can watch midweek games on TV, with Sky Sports showing nearly every midweek EFL match this season on Sky Sports+.
However, because this fixture is a rearranged clash due to clubs progressing to the FA Cup fourth round, midweek broadcast rules do not apply.
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Saints were meant to visit Leicester at 3pm on Saturday, when a blackout is in place. They will instead host Leicester, ironically, in the cup at that time.
And it means that those normal broadcast rules will apply to this rearranged Championship match, now set for tonight, so it will not be shown on TV.
You can stay up to date as the Daily Echo is travelling to the King Power and will bring updates throughout the contest on our dedicated live blog.