Millwall chalked up a second home win in succession on Wednesday night as Birmingham City were defeated 2-0 at The Den.
Jed Wallace and Ben Thompson found the target as The Lions stretched their unbeaten run to seven matches in the League and registered a third straight victory.
Gary Rowett made three changes from the side which defeated Reading 2-1 at the weekend, with goalscorers Matt Smith and Mason Bennett, as well as Jed Wallace, coming in for Shaun Williams, Jon Dadi Bodvarsson and the injured Kenneth Zohore.
The game was only three minutes old when The Lions took the lead, as a defensive lapse allowed Jed Wallace to sneak in and poke the ball past Neil Etheridge in the Birmingham goal.
From there, however, The Blues began to get themselves into proceedings, and with 12 minutes on the clock Birmingham captain Harlee Dean found himself with a chance to shoot inside the penalty area, but his effort was deflected behind, with the resulting corner-kick cleared to safety.
Momentary confusion in the Millwall back-line then presented Maxime Colin with the opportunity to lay the ball back for Lukas Jutkiewicz with Bartosz Bialkowski stranded, but the pass went astray and The Lions got away with it.
In a bizarre twist of events, halfway through the first-half, Jake Cooper - who dislocated his shoulder in the reverse fixture at St Andrews - suffered what seemed to be the same injury and had to be withdrawn. He was replaced by Alex Pearce.
Mahlon Romeo's cross was headed towards goal by Smith shortly after but whilst his attempt did not lack power, it lacked direction, before Scott Hogan's effort at the other end went well wide.
Possession was exchanged in the middle of the park as the half-hour mark came and went, and it was Ben Thompson's determination to win the ball back which created another chance for Millwall, but after Jed Wallace sent through Bennett, his touch was poor and Dean was able to see the ball behind for a goal-kick.
Rekeem Harper was proving the visitor's most potent threat, and he kept his feet despite stumbling due to the close attentions of Romeo on 35 minutes, but his shot was blocked by Ryan Woods. The Blues still came forward in their attempts to equalise, but after Bialkowski punched clear three minutes later, Dean's effort was fired over.
Birmingham began the second-half on the front foot but failed to trouble Bialkowski, with the first Millwall effort going the way of Jed Wallace on 54 minutes as he drilled a free-kick from distance into the wall.
There was a huge talking point in the 57th minute as The Lions broke away with Bennett feeding Smith, but after the striker's cross seemed to be too long for the former, Scott Malone rushed in to strike. His effort was tipped wide by Etheridge, but with Smith seemingly able to tap the ball home from close range on the rebound, a diving Dean came sprawling out to block - whether it was with his hand or not, only those close by or watching a replay could tell, but referee Darren Bond was unmoved.
The Blues were proving a thorn in Millwall's side in an attacking sense and were still pushing for the equaliser as the last half-hour got underway, but after Thompson and Romeo both failed to clear, Jutkiewicz's shot was stopped by a strong Bialkowski arm. Ivan Sunjic then struck over the bar as Birmingham continued to probe.
Jutkiewicz was then perhaps lucky to stay on the pitch after scything Thompson down from behind, but just a few minutes later The Lions were two to the good after a slick move involving Romeo and Shaun Hutchinson, ending with the latter crossing for an unmarked Thompson to strike home and double Millwall's lead.
Malone then blasted into the side-netting from an acute angle as better options were on inside the area, before The Blues had the ball in the net in stoppage-time, but Birmingham substitute Jonathan Leko was deemed to be in an offside position.
Millwall: Bialkowski, Hutchinson, Cooper (Pearce 22'), J. Wallace (Bradshaw 87'), Thompson (Ferguson 87'), Smith (Bodvarsson 70'), Romeo, Malone, Woods, Bennett (Mitchell 71'), Evans. Subs not used: Fielding, McNamara, Tiensia, Burey.
Scorer: J. Wallace 3', Thompson 75'
Booking: Romeo, Woods
Birmingham City: Etheridge, Colin (Bela 81'), Pedersen, Hogan, Jutkiewicz (Leko 81'), Dean, Clarke-Salter, San Jose (Valery 59'), Gardner, Harper, Sunjic (Sanchez 70'). Subs not used: Prieto, Friend, McGree, Toral, Halilovic.
Booking: Harper, Jutkiewicz
Referee: Darren Bond