All you need to know about Monday's game
Whilst Neil Harris' charges enjoyed a 2-0 JPT success at Roots Hall at the beginning of December - their first away win since mid-October - The Lions have started to slip away from the Play-Off spots and are now six points shy with the season approaching the halfway mark.
However such is the tight nature of League One, that a couple of decent results could propel any team up a handful of places in any one given week, and the Millwall camp are determined to finish the year on a winning note and kick on once again in January.
Southend, on the other hand, go into action on Monday fresh from a morale-boosting 2-0 derby win at Colchester United - a result that stretched their unbeaten run in the League to eight games, during which they have taken maximum points on four occasions.
"It's a tough place to go and Southend had a good win at Colchester on Saturday so they will have their tails up. But this is a good group of lads we have got here, they are desperate to succeed and will be giving everything that they can to make sure we get the result we want on Monday."
"There is a quick turn around with the matches, but we will be looking to give Millwall the fright of their lives."
Manager Neil Harris faces a goalkeeping conundrum as David Forde performed admirably between the sticks in the Walsall match during his first League start since August in place of Jordan Archer. However Archer has now sat out the one match ban imposed following his dismissal against Gillingham, leaving Harris with the tough choice as to which keeper to start with at Roots Hall.
Harris, who made five changes to his starting XI against Walsall, could be tempted to freshen things up again in a bid to improve on a disappointing run of results that has seem Millwall beaten in five of their last seven games.
George Saville, Byron Webster, Shaun Cummings and Ben Thompson are just four of a handful of players champing at the bit waiting to get back in the team, but boss Harris has been keeping his cards close to his chest selection-wise ahead of Monday's game.
Southend manager Phil Brown has reported no fresh injury worries ahead of Monday's clash and could name an unchanged team from the same side that beat Essex rivals Colchester United on Saturday, itself the same XI that thumped Bury 4-1 in the Shrimpers last game at Roots Hall.
Ben Coker (groin) and Michael Timlin (heel) could both be vying for a place in the squad as they look to shake off niggling injuries.
However when the two teams last locked horns three weeks ago in the JPT Area Final at Roots Hall, it was The Lions who came away victorious with goals from Steve Morison and Shaun Williams clinching a 2-0 away win. Millwall's last victory in the League at Roots Hall came on 3rd March 2009 courtesy of Gary Alexander's 39th-minute winner.
When arranging your travel for this game please be mindful that various train lines will be subject to closures and/or alterations. However, c2c are providing an additional service to and from Southend Central, located around a 20-minute walk away from Roots Hall, which departs Fenchurch Street at 10.52am and arrives at 11.49am. The post-match service departs Southend Central at 4pm and arrives at Fenchurch Street at 4.58pm. For more information please click here.