Luke Varney netted against his old club eight minutes after coming on as a half-time sub to see the Blues to a hard-fought 1-0 victory over Derby at the iPro Stadium where Town are undefeated in almost a decade. The striker hit a 25-yard shot - the Blues' first on target - which Rams keeper Scott Carson could only help on its way into his net.
Adam Webster and Conor Grant replaced the injured Tommy Smith and Freddie Sears in an otherwise unchanged side but with Town lining up in a 4-4-1-1 formation with Grant on the left and Kevin Bru behind striker Brett Pitman.
Derby made two changes with Jacob Butterfield coming in for Johnny Russell, who has a calf problem, in midfield and Alex Pearce taking over from Jason Shackell at centre-half.
The Blues had most of the ball in the early stages but it was Derby who created the first chance on five, James Wilson breaking towards the edge of the box before Webster stopped him in his tracks.
The Rams went close to going in front in the 10th minute when Luke Chambers’s clearing header from a cross from the right only reached Matej Vydra on the edge of the box. The Czech Republic international hit a powerful low shot which Bartosz Bialkowski brilliantly stopped. Chambers atoned for his error by reaching the loose ball before Wilson
Derby continued to look the more dangerous side with their pace going forward proving a significant threat but without Bialkowski being tested again.
But the Blues began to get on top as the match reached the 20-minute mark, Bru and Jonas Knudsen combining with Grant Ward on the left before the ex-Spurs winger hit a low shot well wide.
On 22 Bru, who was finding a lot of space midway inside the Derby half, fed Grant to his left. The on-loan Everton man crossed to the far post and the ball deflected out to the Mauritius international, whose attempt to loop the ball back into the box was blocked.
Town continued to have more of the ball, passing it around confidently at times, but without creating an opportunity.
In the 31st minute a Butterfield freekick on the Derby right, awarded after Grant had fouled Cyrus Christie, was cleared to Craig Bryson, who hit a shot through a crowd of players which Bialkowski claimed at the second attempt.
The Rams were taking charge again and two minutes later, after Bru had got caught in possession midway inside his own half by Will Hughes, Bryson shot wide, off a Town defender according to the home players but not referee Stuart Attwell.
Town found themselves very much under the cosh as the half entered its final 10 minutes. Chambers blocked an Ikechi Anya shot, then Cole Skuse was booked for a foul on Hughes. Moments later, Webster bundled the ball behind after Anya had cut in from the left.
On 38 Webster made a strong run from deep unchallenged but Derby quickly regained possession and brought the ball forward again.
A minute later Berra was booked for a foul on Hughes and Butterfield sent the resultant 25-yard freekick wide.
The Derby pressure continued, Wilson hitting a low shot from distance which Bialkowski saved down to his left. Knudsen cleared the danger.
Half-time gave the Blues some respite having been pinned back in their own box for most of the final 15 minutes.
After weathering the Rams’ earlier spell of dominance, the Blues briefly got on top but without creating a serious chance. However, the home side regained control and Town will be pleased to have gone in still level at the break.
The Blues made two made two changes at the start of the second half with Varney and Tom Lawrence, making his Blues debut, taking over from Grant, who had never really got to grips with the pace of the game, and Bru, who had drifted out of it towards the end of the half. Lawrence started on the left with Varney joining Pitman up front.
Bryson hit the second period’s first shot wide two minutes after the restart, before Varney picked up a quick booking for a foul on Pearce.
But in the 54th minute the 33-year-old, in his third spell with the Blues having signed a short-term deal until January last month, put Town in front via their first shot on target.
The one-time Ram brought the ball inside from the right and hit a 25-yard shot which Carson could only palm into the corner of his net. The former England keeper will feel he should have done better with Varney’s first goal of his latest spell and third goal overall for Town.
The goal quietened down the home crowd with their side having been unable to replicate their late first-half dominance after half-time. On 61 Butterfield hit a shot which deflected through to Bialkowski.
Five minutes later Lawrence was sent away down the left and crossed accurately with the outside of his right boot to Ward, who headed over.
But the home side gradually began to put the pressure on again. Knudsen did well to cut out Anya’s final ball after some slick Derby passing into the box, then Bialkowski claimed a freekick sent in from left.
Teddy Bishop replaced Skuse in the 72nd minute, the Bristolian having received treatment moments earlier.
Hughes shot not far wide from 20 yards on 75 with the Rams being limited to efforts from distance. Two minutes later, Butterfield hit a strike which hit Webster and then Vydra before going behind.
The Rams began to put the Blues under heavy pressure in the final 10 minutes. On 82 Pitman blocked superbly on the edge of his own box.
Three minutes later, former Town man Darren Bent, who had come on as a sub, blazed over after the ball was played to him on the edge of the box after a cross from the left.
On 87, Berra and then Pitman cleared a dangerous ball in from the Derby right, sending Varney away on the left. Ward made a superb untracked run down the middle but Varney opted to go alone and shot tamely to Carson.
As the match entered its final scheduled minute Pitman was booked for a foul on Hughes, referee Attwell having allowed play to continue after the challenge but with Derby unable to make anything of the attack.
In three minutes of injury time sub Nick Blackman shot not too far wide from 25 yards and seconds before the final whistle the former Reading man came even closer to claiming a point.
Hughes escaped down the left, cut in and crossed low, the ball deflecting to Blackman six yards from goal. The ex-Sheffield United frontman seemed certain to score but Knudsen somehow blocked and Bialkowski grabbed the ball right on his line.
Moments later, referee Attwell’s whistle confirmed Town’s first away win of 2016/17 as a chorus of boos rang around the iPro Stadium.
Having ridden their luck at times towards the end of the first half, once Varney had scored his goal the Blues saw out most of the second period without too much danger until the final moments when Blackman looked certain to score.
The goalscorer will undoubtedly be delighted to have been the hero against one of his old clubs and the former Ram made an impression even aside from his goal and might have created a second for Ward.
The three points sees Town up to ninth in the table with the Blues next in action at home to Aston Villa on Saturday.
Town: Bialkowski, Chambers (c), Webster, Berra, Knudsen, Skuse (Bishop 72), Bru (Varney 46), Douglas, Ward (Lawrence 46), Grant, Pitman. Subs: Gerken, Emmanuel, Kenlock, Best.
Derby: Carson, Christie, Keogh (c), Pearce, Olsson (Blackman 88), Butterfield, Bryson, Hughes, Anya, Vydra, Wilson (Bent 64). Subs: Mitchell, Shackell, Ince, Baird, Johnson. Referee: Stuart Attwell (Warwickshire). Att: 26,425.