Full-time: Derby County sunk by subs as Birmingham City win 3-1 at St Andrew's
A SECOND-HALF turnaround saw Derby County beaten 3-1 by Birmingham City at St Andrew's.
Ben Davies had given the Rams a deserved lead five minutes before the break.
However, substitutes Wes Thomas and Nathan Redmond both struck in the space of eight minutes to put the home side ahead.
Thomas then scored his second in the dying moments to seal the win as Derby pushed for an equaliser.
Manager Nigel Clough named an unchanged starting line-up following the midweek draw away to leaders Cardiff City.
However, defensive duo Kieron Freeman (ankle) and Mark O'Brien (knee) were named on the bench after injury.
The Rams were still without John Brayford (hamstring), Craig Bryson (groin), Jamie Ward (hamstring), Will Hughes (groin) and James O'Connor (knee).
Derby keeper Adam Legzdins, back at his former club, denied Peter Lovenkrands from close range in the fifth minute but the flag was up for offside.
Chris Martin tried to release Conor Sammon after 13 minutes but England international stopper Jack Butland was out quickly to save at the striker's feet.
Birmingham's giant front man Nikola Zigic was winning plenty in the air but he planted a header wide from a Paul Caddis cross three minutes later.
Gareth Roberts robbed Chris Burke in an advanced position and squared for Davies but his low drive from 20 yards was off target.
Davies found his range with a 25-yard free kick but it was straight at Butland.
Martin thought he had his first goal for the Rams after 36 minutes but his 25-yard piledriver was brilliantly tipped over by the flying Butland.
The Rams were on top and they took the lead five minutes before the break.
Forsyth's cross into the box was cleared but the on-loan midfielder headed it back into the area and Davies arrived at full stretch to hook a volley past Butland, who got a touch but could not keep it out.
With Birmingham rattled, Derby might have added a second before half-time but Sammon and Martin were both denied by last-ditch blocks.
In added time, the hosts went close but Legzdins blocked Zigic's far post header following Shane Ferguson's free kick.
Blues boss Lee Clark made a double change at the interval, bringing on Redmond and Thomas for Chris Burke and Lovenkrands.
Derby continued to press and Davies tested Butland with a speculative dipping effort from 30 yards.
The pace of Redmond down the right caused the Rams problems in the 58th minute but his cross just evaded Wade Elliott in the middle.
The hosts now had their tails up and almost equalised just after the hour.
Callum Reilly let fly from 20 yards but his rising shot crashed back off the crossbar.
Moments later, Zigic headed over from close range after great work on the left from Shane Ferguson.
The equaliser eventually came in the 68th minute.
Substitute Ravel Morrison fed Thomas with his back to goal but the striker span and held off the challenge of Richard Keogh to squeeze the ball past Legzdins from a tight angle.
Birmingham then took the lead with a quarter of an hour to go.
After a spell of pressure around the Derby area, Caddis found Redmond 20 yards out and the winger unleashed an unstoppable left-foot shot which flew into the corner of the net.
Derby almost hit back immediately but Jake Buxton's far-post volley from Davies' free kick was parried by Butland.
They nearly levelled in the 89th minute, only for Keogh's downward header from Michael Jacobs' cross to bounce inches wide.
Butland then did well to save at the feet of Sammon from Martin's through ball.
In the second minute of added time, Birmingham got their goal - Thomas with a clinical finish after Redmond had helped on Zigic's flick.
GOALS: B Davies (40) 0-1; Thomas (68) 1-1; Redmond (75) 2-1; Thomas (90+2) 3-1.
BIRMINGHAM CITY: Butland, Caddis, C Davies, Robinson, Ferguson, Burke (Redmond, 46), Reilly (Morrison, 63), Spector, Elliott, Lovenkrands (Thomas, 46), Zigic. Subs: Colin Doyle (gk), Caldwell, Mullins, Fahey.
DERBY COUNTY: Legzdins, Gjokaj, Keogh, Buxton, Roberts, B Davies (Jacobs, 81), Coutts, Hendrick, Forsyth, Martin, Sammon. Subs: Fielding (gk), Freeman, Hoganson, O'Brien, Conor Doyle, Bennett.
REFEREE: S Hooper (Wiltshire).
ATTENDANCE: 15,850 (1,317 away fans).
BOOKINGS: Birmingham - Ferguson (85) foul on Gjokaj; Zigic (85) foul on Jacobs.