Paul Charnley's side know they will need to be on top of their game for this two legged affair. However, the Sphinx boss has a number of injury worries ahead of the game tonight which kicks off at Sphinx Drive at 7,45pm.
Adie Fisher and Kyle Rhodes appear to be definitely out whilst there are concerns about former Sky Blue Tom Bates and the son of former Sky Blue James Holmes.
Admission is £5 for adults and £2.50 concessions. The game will be part of our Match Night Live coverage.
The second leg at Coalville is on April 1st and the final will be played at Walsall FC's Bescot Stadium.
Coventry Sphinx Reserves are also in cup action tonight. Lee Knibbs side travel to Coleshill Town in the second leg of the Challenge Trophy. The first leg on Saturday finished 2-2.
Sphinx are at home to Boldmere St Michaels on Saturday in a league game. If you are not going to see City at Southampton, why not pop down and watch the game whilst listening to how the Sky Blues are getting on.