While the Lions were forced to share the spoils with Bristol City last time out, the Millers were condemned to defeat away against Huddersfield Town.
Match preview
Millwall played out their third successive draw at The Den when they picked up a point in a goalless stalemate with Bristol City on Thursday night.
Gary Rowett's men, who struggled to pose a real threat in the final third, failed to register a single shot on target against the Robins and another draw on home soil has now seen them drop out of the playoffs to eighth place, albeit level on points with Middlesbrough in sixth having played a game less.
Millwall have at least shown their resilience when playing in front of their own fans as Thursday's draw extended their unbeaten home run to seven matches in the Championship, and the Lions will be optimistic of securing at least a point in their next encounter against Rotherham.
Indeed, Millwall have avoided defeat in each of their last four league meetings with Rotherham and are unbeaten in their last two against the Millers at The Den, including a slender 1-0 win in April 2021.
Rowett, meanwhile, has had plenty of success of his own against Rotherham as he has lost only one of his last 11 league matches against them as a manager, which bodes well for the Lions ahead of their first fixture in 2023.
Rotherham's poor run of form continued on Thursday night when they suffered a 2-0 defeat away against basement club Huddersfield, a result which helped the Terriers move off the foot of the table.
Strikes either side of half time from Duane Holmes and Jordan Rhodes condemned the Millers to their 10th Championship defeat of the season, with eight of those losses under new head coach Matt Taylor, who replaced Paul Warne in October.
Rotherham continue to slip down the Championship standings and they are now positioned in 20th, just two points above the relegation zone having played a game more than Huddersfield in 22nd place.
The Millers head to The Den with the third-worst away record in the Championship so far this term, winning only two of their 13 matches on the road. Taylor will be hoping to see quick signs of improvement on their travels as three of their next four fixtures in all competitions are away from home.
With challenging encounters on the horizon against Blackburn Rovers, Watford, Sunderland and Sheffield United - who are all inside the top five at present - Rotherham will be keen to begin the New Year on a positive note by claiming maximum points against an inconsistent Millwall outfit on Sunday.
Millwall Championship form:
D
W
L
D
W
D
Millwall form (all competitions):
W
D
L
D
W
D
Rotherham United Championship form:
W
D
L
L
D
L
Team News
Millwall midfielder Ryan Leonard has returned to light training following a lengthy spell out with a hamstring injury, but it remains to be seen whether he will be involved on Sunday.
The Lions have been boosted by the return of Callum Styles, however, who came off the bench against Bristol City after recovering from a calf strain, and the former Barnsley man will now be pushing to start in midfield.
After failing to fire in front of goal last time out, striker Tom Bradshaw could be replaced by Benik Afobe, while Zian Flemming is expected to continue in the number 10 role.
As for Rotherham, striker Tom Eaves was forced off in the 20th minute against Huddersfield with an injury and is expected to miss out on Sunday, with Conor Washington the most likely candidate to replace him up front.
The Millers will also be without Ben Wiles (ankle), Georgie Kelly (calf) and Grant Hall (hamstring) due to injury, with all three players hoping to return towards the end of January.
Richard Wood could be recalled at centre-back at the expense of either Jamie McCart or Cameron Humphreys, while Brooke Norton-Cuffy will likely replace Peter Kioso at right wing-back.
Millwall possible starting lineup:
Long; McNamara, Hutchinson, Cooper, Wallace; Mitchell, Saville; Voglsammer, Flemming, Burey; Afobe
Rotherham United possible starting lineup:
Johansson; Harding, Wood, Humphreys; Norton-Cuffy, Lindsay, Barlaser, Rathbone, Bramall; Washington, Ogbene
We say: Millwall 1-0 Rotherham United
A closely-fought contest is set to be played out at The Den, but Millwall will be regarded as slight favourites to come away with all three points.