Boro come into this fixture off the back of a routine win over struggling Wycombe Wanderers and will be keen to keep their playoff charge going against City on Saturday.
Neil Warnock's side have been heavily affected by COVID-19 in recent weeks, which meant putting out a weakened team against Brentford - a closely-fought match that they went on to lose.
Since then, Warnock will have been pleased to hear that no new positive cases have emerged after the latest round of test results came through on Monday. With that, the Boro boss will be hopeful of having a more familiar first team ready for Saturday.
Boro will be hoping to secure their fifth straight home win against the Blues - a record that they last achieved back in 2018 under Tony Pulis, who recently left Sheffield Wednesday after only 45 days in charge.
Home form has been a major feature of Boro's success so far this season - having lost only one game and won seven - and Warnock will be confident his side can build on that record against a side who they beat 4-1 away from home just before Christmas.
Albeit a fan-favourite during his time with Boro, the Smoggies will want nothing more than a win over Karanka on Saturday to put pressure on the teams around them, who play in the later kickoffs.
Despite sitting 19th in the Championship table, Karanka remains relaxed over his future as Birmingham City boss, but will be aware that results will need to come sooner rather than later, given their torrid run.
No win in eight, and no goals in their last three, leaves the Blues dead last in the form table with only one point secured in their last six.
It is hardly the sort of form that Middlesbrough will fear, but such is the unpredictability of this league, no team can become complacent at any stage of the season.
That said, Middlesbrough have lost only one of their last 20 home games against Birmingham in all competitions - that loss came by way of a 2-1 defeat last season when Pep Clotet was in charge of the Blues.
Middlesbrough Championship form: LWWWLW
Middlesbrough form (all competitions): LLWLWL
Birmingham City Championship form: WLLLDL
Birmingham City form (all competitions): LLLDLL
Marcus Browne will not be available for selection after being stretched off in the Boro's 2-1 FA Cup loss to Brentford last weekend.
It is not yet known how long his dislocated kneecap will keep him sidelined for.
Meanwhile, Ashley Fletcher is nearing a return and has an outside shot of featuring in this one, though it is likely that this match has come a bit too soon for the former West Ham marksman.
First-choice goalkeeper Neil Etheridge could also come back in between the sticks after sitting out the cup tie.
Middlesbrough possible starting lineup:
Bettinelli; Dijksteel, Fry, McNair, Bola; Wing, Saville, Morsy, Johnson, Watmore; Assombalonga
Birmingham City possible starting lineup:
Etheridge; Colin, Roberts, Dean, Friend; Clayton, Sunjic; Sanchez, Toral, Bela; Jutkiewicz
We say: Middlesbrough 3-0 Birmingham City
Nearly all roads lead to a Boro win on Saturday, with the home side clearly in a good place when playing at the Riverside, and City seemingly struggling to keep goals out at one end and score at the other. We expect Boro to come away with a convincing win.