Lee Bowyer scored his first goal for almost 12 months to give Birmingham a shock 1-0 victory over Chelsea at St. Andrew's.
Birmingham keeper Ben Foster produced a superb performance as the Barclays Premier League leaders suffered a successive defeat.
Foster, who was the hero for Alex McLeish's side - while Didier Drogba headed against the bar for the away side, bounced back from his error on England duty in midweek with a series of stunning saves.
Foster made a fine save to keep Birmingham on level terms after Didier Drogba was sent clear by Salomon Kalou.
But Birmingham stunned Chelsea by taking the lead via their first worthwhile attack after 17 minutes. Sebastian Larsson's right-wing cross was headed down by Cameron Jerome to Bowyer who was completely unmarked and hit the ball past Petr Cech.
Foster went down to his right to hold onto Drogba's effort and then made a superb reflex save to keep out Drogba's close range header from Nicolas Anelka's centre.
Drogba tried his luck with a low 30 yard free-kick and Foster was again alert to turn it around the post. But he was helpless after 38 minutes when Drogba crashed a header against the crossbar from Florent Malouda's cross.
Roger Johnson produced a superb tackle to stop Ramires after his run into the box and needed treatment to his knee before being able to continue. Kalou turned back inside but he curled his shot over the bar with Foster off his line.
The chances started to come again for the visitors with Foster holding onto a Drogba free-kick and Kalou heading wide from Anelka's cross.
Scott Dann's back pass played in Kalou but Foster took the ball away from his feet with a perfectly timed challenge and Foster then parried aside an Branislav Ivanovic header as the home side held on for a vital win.
Copyright (c) PA Sport 2009, All Rights Reserved.