Iain Dowie's Crystal Palace side must simply love playing against teams from the West Midlands.
Palace, promoted via the play-offs last season, have taken six points off Blues this term and another four off both West Bromwich Albion and Aston Villa.
Given Palace only have 25 points in total, it is remarkable they accumulated over 50 per cent of their tally at the expense of the triumvirate of Premiership sides from this region.
The statistic must be particularly galling for Birmingham City manager Steve Bruce, who quit Palace in controversial fashion to take over at St Andrew?s in December 2001.
After seeing his side mugged at home by Palace earlier in the campaign, Bruce was hoping to build on Birmingham?s recent victory against Liverpool with another impressive display at Palace.
However, Blues? inability to perform consistently well from one week to the next continues to stifle their Premiership season.
No-one is more exasperated than Bruce, who has experimented with numerous different players to try and hit on a winning formula.
But with just ten games remaining, Bruce ? whose best laid plans have been decimated by injuries this season ? appears no nearer to solving the problem.
The long-term absence of David Dunn and the loss of talisman Robbie Savage to Blackburn Rovers has been significant.
And Blues sorely missed the suspended Emile Heskey and Mario Melchiot, who was injured, at Selhurst Park.
Yet Birmingham still should have had enough class to dispose of a workmanlike Palace side, who rely heavily on former Blues striker Andy Johnson in attack.
Birmingham did create four decent first half openings but they never looked like getting anything out of the game following Johnson?s 41st minute opener from the penalty spot.
Bruce said: ?In the first half, I thought we were the better team and we?ve created the better opportunities.
?We?ve had some good chances after ten or 15 minutes with a Matthew Upson header and Clinton Morrison has had a glorious chance from which he should have scored.
?But at this level you know you?re not going to get too many chances so you?ve got to take them.
?In the second half I was looking for us to improve and go on but unfortunately we didn?t. We went out with a whimper and that really upsets and saddens me particularly after playing so well against Liverpool.
?We were very poor and simply not good enough and I?ve let a few of them know in no uncertain terms that I?m not happy
?It baffles me and I?m left scratching my head as to how we can put two or three good performances together and then come down to this level which was awful.?
The defeat means Blues have now lost five successive matches away from home, starting with their reverse at Newcastle United on New Year?s Day.
And Bruce knows he will have to inspire a muchimproved display from his players if they are to avoid an embarrassing result at neighbouring West Bromwich Albion ? who prop up the table ? this Sunday.
The return of Heskey will certainly help because his stand-in, Morrison, was poor at Palace before being substituted in the 63rd minute.
The ex- Palace forward endured an afternoon to forget back on his old stomping ground as he shot wide when clean through and he also managed to deflected Walter Pandiani?s goal-bound header wide.
In fact, up until the Palace penalty opener, Blues were very comfortable but they never really recovered from the shock of failing behind four minutes before half-time.
Tom Soares won the spotkick with a dash into the penalty area that was ended when Matthew Upson and Kenny Cunningham sandwiched Palace?s young midfielder and referee Phil Dowd blew for a penalty.
Johnson scored with his first attempt down the middle and when he was ordered to re-take the kick for encroachment he calmly planted the ball into the corner.
Birmingham?s players protested vigorously against the penalty decision and their sense of injustice heightened after the break when Johnson won the hosts? second penalty following very slight contact with Upson.
Johnson dispatched the penalty with aplomb once more ? much to the frustration of Bruce, who felt both decisions were dubious.
Bruce said: ?Maik Taylor hasn?t had a save to make apart from the two penalties. They were soft penalties, to get one against you is bad enough but to get two is very disappointing.?
Indeed, it was a very disappointing afternoon all round for Bruce and his players. Even the enigmatic Pandiani, on his fourth start for the club, was virtually anonymous after the interval as the heavy pitch took its toll.
Birmingham, who won back-to-back derby matches against Albion and Aston Villa earlier in the season, must hope to do so again if they season is not to fizzle out.
Scorers: Johnson (pens, 41, 68).
Crystal Palace (4-4-2): Kiraly; Boyce, Hall, Sorondo, Granville; Routledge (Lakis, 90), Leigertwood, Hughes, Soares (Borrowdale, 90); Johnson, Freedman (Torghelle, 87). Subs: Speroni, Kolkka.
Birmingham City (4-4-2): Maik Taylor; Tebily (Anderton 73), Cunningham, Upson, Clapham; Pennant, Clemence, Johnson, Gray; Pandiani, Morrison (Blake, 63). Subs: Vaesen, Diao, Nafti.
Referee: P Dowd (Staffordshire).
Bookings: Birmingham ? Pennant, Pandiani (fouls), Morrison (dissent); Palace ? Leigertwood, Hughes, Soares (fouls).
Attendance: 23,376.
Blues man of the match: Damien Johnson - admirable work ethic.
