John Eustace's side dispatched of Queens Park Rangers last time out in front of their home faithful, whereas Millwall's winning run ended with defeat away at Huddersfield Town.
Match preview
A record attendance at St Andrew's since fans returned after the Covid-19 pandemic saw Birmingham earn three points against Michael Beale's high-flying R's courtesy of first-half goals from Auston Trusty and Manny Longelo.
Blues had to defend resolutely in the second period and will be thankful for a magnificent penalty save from goalkeeper John Ruddy, but Eustace's men secured a maximum and moved up to 12th in the Championship standings after an impressive display.
The Second City club are amongst the form teams in the second tier, having won five and drawn three of their last 10 Championship fixtures, a positive record everyone associated with the team will hope to continue as they try to distance themselves from a relegation battle many neutrals envisaged for them this campaign.
Birmingham's league-leading defensive record has been the foundation on which a talented and hungry set of players have built on this season, with the team only being breached 15 times in 17 league matches so far, fewer than even Burnley and Sheffield United.
With three of their last four games before the World Cup break in front of their own fans, Blues will be sensing a real opportunity to carry on building a positive connection between the players and the supporters, with the best way to do that being getting results on the football pitch.
Gary Rowett's Lions could not make it five wins on the bounce as they fell to defeat at the John Smith's Stadium against Huddersfield on Saturday, but the head coach is remaining level-headed and admitted even four straight wins in the Championship is not a feat many clubs will achieve this season.
Despite their blistering recent form, it may not have come as a complete surprise to the travelling supporters on the weekend that their team were unsuccessful, as Millwall have only won one of eight matches away from The Den this campaign, with only Middlesbrough and Huddersfield possessing poorer away records.
The Londoners will have to improve on their ventures if they are to achieve a top-six finish this year, and get an immediate opportunity to do so when they travel to Birmingham on Wednesday, a place where they last tasted victory in March 2019.
In fact three of Millwall's last four league games before the World Cup are away from home, so Rowett will need to find a way to get a tune out of his side on the road if they are to shorten the two-point gap between themselves and Swansea City in sixth place.
Birmingham City Championship form:
L
W
W
D
L
W
Millwall Championship form:
D
W
W
W
W
L
Team News
Birmingham City defender George Friend could make his return to the matchday squad after a few months out with a calf injury, although the 34-year-old is unlikely to break into the starting XI anytime soon given the performances of left-sided defenders Trusty and Longelo.
Nico Gordon will get gametime for the Under-21s this week as he continues his comeback from an unspecified health issue that has seen him play no part so far this campaign.
Millwall's George Saville was the only outfield player not utilised in the game at Huddersfield, sparking questions about his fitness which Rowett answered by explaining that the midfielder was not brought on as his side chased the game for tactical reasons.
The Lions remain without defender Ryan Leonard with a hamstring injury - the 30-year-old has not played since the defeat at Norwich City back in August.
Birmingham City possible starting lineup:
Ruddy; Sanderson, Dean, Trusty, Colin, Bielik; Hannibal, Longelo, Chong; Deeney, Hogan
Millwall possible starting lineup:
Long; McNamara, Cresswell, Cooper, Malone; Shackleton, Mitchell, Burey, Flemming, Styles; Bradshaw
We say: Birmingham City 1-0 Millwall
Birmingham City are full of confidence heading into this clash with Millwall and could move as high as seventh with a win.