Just one goal separates the two sides at present as both clubs sit on 33 points in the table, one point short of Ipswich Town in sixth spot, illustrating the importance of this encounter.
Wednesday head into the clash boasting a superb run of seven games unbeaten at Hillsborough, with their latest home game ending in a convincing 4-1 win over Wolverhampton Wanderers.
Birmingham have been equally impressive on their travels, boasting a record of five wins and four draws in 11 away games – bettered only by Middlesbrough, Derby County and Ipswich.
There will be a few key absences through injury for both sides, but at full strength a combined eleven between the two would make for quite a formidable outfit at Championship level.
As seen by the graphic above, here is what a combined side between the two play-off contenders would look like with Wednesday boasting six players and Birmingham five.
One potential weakness in both teams is the amount of goals shipped this season – 50 combined – but that does not mean they do not have quality players at the back.
Kieren Westwood is a reliable goalkeeper at Championship level while Jack Hunt and Tom Lees have both been solid for the Owls, the latter a key absentee through injury at present.
Birmingham’s Michael Morrison and Jonathan Grounds make up the back four, and both have been excellent this season with Grounds in particular a real standout player at St. Andrews.
Wednesday struck one of the deals of the summer in signing Barry Bannan from Crystal Palace, while Stephen Gleeson has also been superb this season, scoring three and adding a further three assists.
Demarai Gray has lived up to his billing as one of the league’s outstanding talents, and Carlos Carvahal’s men will have to watch him carefully on Boxing Day as he has ability in abundance.
The exceptional Fernando Forestieri will be keen to continue his fine form, scoring eight and adding three assists in 16 league matches, while Ross Wallace gives the Owls great width on the right.
Target man Clayton Donaldson completes the team, scoring five and adding six assists this season, but he could be missing for Gary Rowett’s side as he continues to recover from a groin injury.