Leicester's winless run stretched to nine matches after Birmingham scored a last-gasp penalty to earn a 2-2 draw in the Championship.
Hosts Leicester took the lead after 12 minutes at King Power Stadium when Curtis Davies headed into his own net.
Birmingham had to wait until 15 minutes after half-time to find their equaliser with Nikola Zigic squaring matters, the Serbian forward tapping into goal following a slick build-up.
Nigel Pearson's men reclaimed the advantage with a quarter of an hour to play when Jeffrey Schlupp powered a header into goal from a corner.
There was still time for some late drama, however, following David Nugent's foul on Wes Thomas inside the penalty area on 91 minutes.
Chris Burke stepped up to slot the penalty home and salvage a second consecutive draw for Birmingham, who sit in 13th place on the standings.
Leicester stay out of the playoff places in seventh on 61 points, one point shy of sixth-place Brighton & Hove Albion, who travel to Middlesbrough on Saturday.