At a time when the Lions sit three points adrift of fourth spot, Swansea are down in 17th place in the standings after losing four of their last five fixtures.
Match preview
On the back of losing to direct rival Norwich City last time out, Gary Rowett knew that his side needed to respond with maximum points at Reading at the weekend.
Although it took an early penalty to make the difference versus the Royals, Rowett and his players will not care as they ensured that they remained on the coat-tails of the teams above them.
Remarkably, Millwall have still not posted back-to-back victories since October, a bizarre statistic when they could move as high as fourth position come the full-time whistle on Tuesday.
On a more positive note, the Lions have scored in nine of their most recent 10 matches, a record which will not be lost on a struggling Swansea side.
When the teams met in the reverse fixture back in August, Swansea scored two own goals to gift Millwall a share of the spoils in South Wales.
That has been the story of Swansea's season, and Russell Martin cannot be happy with the trajectory of what remains a talented squad.
Martin would have been delighted to be leading in-form Middlesbrough at half time on Saturday, only for his team to ship three goals in 23 second-half minutes.
While plus points can be taken from troubling such a relentless outfit, Swansea have now prevailed in just three of their last 20 fixtures in the second tier.
Sitting 11 points clear of the drop zone, Swansea should be safe from relegation zone if they pick up points here and there, although is not necessarily a certainty based on their short and long term form.
Millwall Championship form:
W
D
W
D
L
W
Swansea City Championship form:
W
L
L
D
L
L
Team News
Rowett could opt to stick with the Millwall XI which started the hard-fought victory at Reading.
If a change is made, it may be to introduce fresh legs in midfield with Jamie Shackleton in contention to replace either Ryan Leonard or George Saville.
The latter avoided a booking at the weekend, and the lack of caution last time out means that he is no longer under threat of collecting 10 yellow cards at the cut-off point.
Joel Latibeaudiere and Jay Fulton both hit double figures for bookings on Saturday, leaving them out of contention until after the international break.
Harry Darling and Olivier Ntcham appear most likely to earn recalls, with Luke Cundle dropping deeper providing that Joe Allen misses out through injury as expected.
Millwall possible starting lineup:
Long; McNamara, Cresswell, Cooper, Wallace; Leonard, Saville; Honeyman, Flemming, Voglsammer; Bradshaw
Swansea City possible starting lineup:
Fisher; Cabango, Wood, Darling; Sorinola, Grimes, Cundle, Manning; Ntcham, Cooper; Piroe
We say: Millwall 2-0 Swansea City
After losing their last home fixture, Millwall will be determined to put things right on Tuesday. That is not the ideal scenario for the visitors, who we feel will be unable to withstand their hosts in East London.