The Boro will be desperate to get back to their good home form as they have lost their last two fixtures at the Riverside, losing to Birmingham City and Blackburn Rovers.
The Millers have only played two games in the Championship in January, which has resulted in them being unbeaten this month, after drawing 3-3 in a classic against Stoke City last time out, as well as getting their second away win of the season against Derby County.
We are slightly over halfway through the season, but this game is a massive three points for each side to try and achieve their goals for the season.
Middlesbrough sit three points away from the final play-off spot, currently sat in seventh. Rotherham United are deep down the table sitting in 22nd, five points adrift from Wayne Rooney's Derby County, but the Millers have three games in hand on the Rams.
Boro midfielder Dael Fry is being closely monitored having received several stitches following a boot to the face from a Blackburn Rovers defender at the weekend, while Marcus Tavernier was another casualty of the defeat, limping off in the latter stages.
Defender Grant Hall and forward Marcus Browne remain on the sidelines, whilst Ashley Fletcher could play more minutes as he returned from injury on the weekend.
Ryan Giles arrived from Wolverhampton Wanderers to become Paul Warne’s first signing of the January transfer window this week, the 21-year-old has put to pen-to-paper on a loan deal which will see him remain with the Millers until the end of the 2020/21 Sky Bet Championship campaign.
This game should be too soon for Giles though, as Rotherham have had a whole week to prepare for this game, Warne may opt to play the same side they did against Stoke.
Bettinelli, Spence, Wood, McNair, Bola, Morsy, Howson, Saville; Tavernier, Assombalonga, Johnson.
Blackman, Ihiekwe, Wood, MacDonald, Olosunde, Lindsay, Barlaser, Wiles, Harding, Crooks, Smith.
Ones to watch
This certainly could be a game for Congolese forward Britt Assombalonga to add a some goals to his tally this year. The 28-year-old only has five goals to his name in the Championship this season, but on his day he can be unstoppable, and this could be a game for the Boro striker to score some goals.
Englishman Matt Crooks bagged two goals in their last game out against Stoke, which doubled his season's tally to four goals this season in the league, the attacking midfielder could be the man to make the Millers tick on Wednesday night.
The sides have faced each other six times since 2014, with Middlesbrough coming out on top winning four times, including the last game out, back in May 2019, coming away 2-1 winners. Rotherham defeated Boro back in 2016 1-0.
The two teams have faced each other 38 times in their club's history since their first meeting in 1954. The Millers haven't defeated Middlesbrough on their turf since 1965, when it was a classic at their old ground Ayresome Park, where Rotherham came away 5-3 winners.
How to watch
You can watch the match by purchasing an iFollow match pass from either club's website.
Boro boss Neil Warnock has become frustrated with signings this month as he's failed to get players in before the game vs Rotherham.
Warnock said: “There are gaps in certain areas and we’re getting punished for it. We’re not close at all really (to new signings). The two lads I thought we’d a great chance with last week, I’ve been told by both Premier League managers in the last 24 hours that they are not letting them out.
“It’s been a devastating week for us on top of everything else.”
Millers gaffer Paul Warne spoke to club media on the upcoming challenge against Middlesbrough, he said:
“We feel like we’re in a really good place and good form and we’ve been playing really well, however all the other team in the bottom seven are picking up points as well. The lads are confident in how they are playing and look really comfortable in the shape at the moment, so we go into the game full of belief.
“We know we can compete with the best teams on our day and in fairness to Middlesbrough they are only one win off the play-off places, so are they are a formidable side. We know how hard they are going to be to play against and the problems they will cause, but after recent performances we can take confidence into the game.”