Cardiff closed the gap on their Championship promotion rivals as Kenny Miller's ninth goal of the season secured a 1-0 win over 10-man Birmingham on Sunday.
The Bluebirds are now back in third place in English football's second tier and lie just three points behind West Ham in the race to land an automatic promotion spot.
The turning point at the Cardiff City Stadium came in the 63rd minute when Birmingham defender Curtis Davies was sent off after he brought down Miller when the Scotland striker was clean through on goal.
Miller capitalised on another moment of casual defending, this time by Birmingham centre-back Pablo Ibanez to fire past Boaz Myhill after 68 minutes to give the Bluebirds their sixth consecutive home win and extend their unbeaten run in all competitions to 10 matches.
Peter Whittingham hit a post with a rasping free-kick, before firing inches wide from the edge of the box, as the Welsh outfit kept pushing for a second goal in the closing stages.