Birmingham winger Chris Burke struck at the death to give Chris Hughton's side all three points against Championship strugglers Burnley.
Burke slotted home a David Murphy cross in the 91st minute to lift Blues to eighth in the table.
Jean Beausejour had opened the scoring, reacting quickest to a rebound after Burnley goalkeeper Lee Grant had turned the ball onto his own bar.
Marvin Bartley had equalised from a Ross Wallace corner after half-time.
Hughton's men dominated the opening exchanges with Beausejour giving Birmingham the lead in only the second minute when, after great work by Zigic and Burke down the right, Burke's shot was saved by Grant only for Beausejour to rifle home the loose ball.
On-loan Burnley striker Sam Vokes then saw a long-range shot graze the right-hand post before Keith Treacy tried his luck from 30 yards.
But Birmingham continued to press with Zigic looking the most dangerous, latching onto the end of a David Murphy free-kick only to see the ball trickle wide.
The Serbia international then set up Marlon King after he unselfishly played the ball across to the big frontman, but King could only slice the ball wide with the goal at his mercy.
Barely four minutes after the break, Eddie Howe's side were level when Wallace's corner was headed out by Curtis Davies straight to the boot of Bartley, who volleyed in a deflected shot beyond Boaz Myhill.
Keith Fahey then had a shot go wide after David Edgar had cleared from a Burke corner, before Zigic again saw two headers in quick succession go inches over the bar.
In a frenzied final few minutes, after Nathan Redmond and Murphy combined to find Burke, the lively winger slotted home the winner.
The result extended Birmingham's unbeaten home run to eight games, while at the same time condemning Burnley to their fourth consecutive league defeat.
Birmingham manager Chris Hughton: "We left it very late but the plus to take from it is the fact there is a lot of spirit in the camp and they are a determined group of players.
"We certainly didn't make life as easy for ourselves as we should have done but I was very happy with some of our offensive play.
"We just need to make sure we start working the opposition goalkeeper more than we are doing at the moment."
Burnley manager Eddie Howe: "It's the second time in a row and it's really frustrating to be beaten by a late goal again.
"This one feels worse than Saturday because I thought we had done enough to get a point which would have been a great point here.
"We played well, defended very well but conceded right at the end and it is a really tough one to take."