ALBION pulled off a stirring comeback to earn a crucial point in a white-hot atmosphere at The Hawthorns.
The Baggies, who began the day two points clear at the top of the table, made the worst possible start with Paul Parry finding the back of the net within 29 seconds.
The same man doubled the Bluebirds' lead in the 33rd minute but super-sub Roman Bednar gave the hosts a lifeline a minute later, taking his season's tally into double figures.
Tony Mowbray's men looked the stronger side after the break but got caught by a sucker punch when Joe Ledley restored City's two-goal lead.
But Albion's never-say-die attitude saw Martin Albrechtsen peg another goal back 20 minutes later - his second of the campaign - and Roger Johnson's 87th-minute own goal completed quite a fightback from the Championship leaders, who could even have pinched all three points thorugh Zoltan Gera at the death.
Mowbray made three changes to his side as he welcomed back 16-goal top scorer Kevin Phillips fom his midweek rest to partner Ishmael Miller in attack, in place of Bednar, who found himself among the substitutes.
Chris Brunt and Robert Koren were restored to midfield, with James Morrison and Gera dropping to the bench.
The Bluebirds took a somewhat fortunate lead within 29 seconds of the start as Parry's 20-yard effort took a deflection to spin over a helpless Dean Kiely's head.
Things went from bad to worse for the Baggies in the 13th minute when ten-goal Miller was forced off after injuring a hamstring as he chased down a Filipe Teixeira pass in a race with Glenn Loovens.
The on-loan hotshot was replaced by Czech hitman Bednar.
Teixeria showed a piece of magic in the penalty area four minutes later to leave Tony Capaldi for dead - but Loovens managed to make a last-ditch challenge to prevent the Portuguese ace getting a shot away.
Robert Koren squared the ball to Phillips with a quick free-kick in the 25th minute and the in-form striker struck a 30-yard exocet, which looked to be heading for the top left-hand corner of the net until Michael Oakes flung himself to his right to save.
City suffered a set-back of their own in the 32nd minute when Kevin McNaughton was forced off with an injury following a challenge with Bednar and was replaced by Darcy Blake.
The stop-start nature of the encounter seemed to be unsettling Albion more than the visitors and in the 33rd minute Parry raced onto Jimmy-Floyd Hasselbaink's flick-on from Blake's long punt and out-stripped Pele for pace before slotting home past Kiely from the narrowest of angles.
The Baggies, however, gave themselves a lifeline just a minute later when Jonathan Greening lofted in a right-wing free-kick to the back post for Bednar to steal in and power home with his head.
Carl Hoefkens neatly controlled the ball on his chest in the 40th minute and came inside Capaldi before letting fly with a swerving right-foot volley that flew just past the right-hand angle of post and bar.
The hosts were close to levelling the scores two minutes later as they came strongly back into the game.
Bednar picked up the ball on the left and floated a cross to the back post where Hoefkens' goalbound header was blocked by Capaldi.
Albrechtsen spared Greening's blushes in the third minute of stoppage time as the Albion skipper inexplicably headed back towards his own goal and allowed Peter Whittingham to steal in.
Fortunately Danish international Albrechtsen read the situation quickly and managed to get a vital touch to deny the former Villa winger a shot before Parry blazed the rebound over.
The Baggies started the second-half on the attack and Phillips looked set to tuck home Brunt's low left-wing cross in the 48th minute until Johnson made a crucial interception.
Seconds later Pele nodded down Teixeira's left-wing corner at the back post and Phillips just couldn't force the ball home allowing a combination of Capaldi and Oakes to clear off the line.
A quickly-taken Brunt free-kick at one end suddenly sprung a Bluebirds attack in the 52nd minute that culminated in Parry finding Joe Ledley, who slotted home across Kiely and into the bottom right-hand corner.
Mowbray made a bold double change five minutes later as Gera and Morrison replaced Koren and Pele respectively.
Brunt switched to left-back with Albrechtsen tucking in alongside Leon Barnett at centre-half, while Morrison and Gera took up places on the flanks and Teixeira moved into the centre of the park alongside Greening,
Albion looked to have put themselves back into the game in the 64th minute when Bednar flicked on Hoefkens' throw from the right and Phillips nodded it over the line, only for the attempt to be ruled out for off-side.
Moments later Bednar flashed a header just wide of the far post from Hoefkens' right-wing centre.
Bednar got an even better opportunity in the 69th minute as he powered in on Brunt's left-wing cross but directed his header wide of the right-hand upright from close range.
Three minutes later Phillips saw his header from Brunt's left-wing flag-kick scooped off the line by Oakes.
Morrison picked up the loose ball and found Brunt, who delivered a second cross that Albrechtsen headed in off the underside of the crossbar from 12 yards.
Ten minutes from time Teixeira swivelled in the box and sent a skidding shot inches past the right-hand post.
Five minutes later Bednar miscued his shot as he reacted quickest to Greening's drive into the danger area.
Gera stole in at the back post from Morrison's left-wing cross in the 86th minute - but the Hungary international headed straight at Oakes.
A minute later Gera played the ball in and the unfortunate Johnson got a touch that looped the ball over former Wolves stopper Oakes and into his own goal.
Gera was in the action again at the death and was unlucky to see his powerful angled volley flash a whisker past the left-hand post with Oakes beaten.
ALBION (4-4-2): Kiely; Hoefkens, Barnett, Pele (Morrison 57), Albrechtsen; Teixeira, Koren (Gera 57), Greening, Brunt; Miller (Bednar 13), Phillips. Subs not used: Steele (gk), Hodgkiss.
CARDIFF (4-4-2): Oakes; McNaughton (Blake 32), Loovens, Johnson, Capaldi; Whittingham, Rae, McPhail, Ledley; Parry, Hasselbaink (Thompson 73). Subs not used: Enckelman (gk), Purse, Ramsey.
BOOKINGS: ALBION - Greening (foul 80).
GOALS: ALBION - Bednar (34), Albrechtsen (72), Johnson (og 87); CARDIFF - Parry (1, 33), Ledley (52).
REFEREE: K Friend (Leicestershire).
ATTENDANCE: 22,325.
ALBION STARMAN: Roman Bednar.
PIC: ROMAN THE CONQUERER...Bednar celebrates giving Albion lifeline with his 34th-minute header
