Britt Assombalonga’s 43rd minute penalty has given relegation-threatened Nottingham Forest a 1-0 half-time lead over the Blues at half-time at the City Ground.
Danny Rowe and Dominic Samuel came into an otherwise unchanged Town side for the injured Tom Lawrence (ankle) and David McGoldrick (neck).
The Blues, who hadn’t won at the City Ground since December 1999, lined up in a 4-3-3 system with Samuel in the centre and Rowe on the right with Freddie Sears on the left.
Town named second-year academy scholar Flynn Downes, a central midfielder, among their subs for the first time, while centre-half Adam Webster returned to the 18 for the first time since injuring his ankle in January.
The home side went into the match fourth from bottom but ahead of Blackburn in 22nd by a goal difference of just one.
Rovers were at Brentford, while Birmingham, who play Bristol City away, are one place and two points above Forest with a significantly poorer goal difference.
The home side made an explosive start to the game, with a Jamie Ward cross from the right deflecting off Christophe Berra, who could well have been playing his final game for the Blues, in the opening seconds but just beyond Britt Assombalonga, who netted after only 17 seconds of Forest’s 2-0 win at Portman Road earlier in the season.
The East Midlanders kept up the early pressure with the Blues pinned back inside their box and with Grant Ward and skipper Luke Chambers both blocking strikes before Jamie Ward curled an effort not too far wide of Bartosz Bialkowski’s left post.
But Town, wearing their white away shirt and blue home shorts, quickly got into the game and began to control possession. On seven, Rowe cut in from the right and hit a shot through to Forest keeper Jordan Smith.
Two minutes later, Grant Ward brought the ball in from the left and hit a powerful 20-yard shot which Smith did well to save down to his left. Samuel was unable to get to the rebound.
As the game moved into its 10th minute, news that Blackburn had gone a goal in front at Brentford filtered around the City Ground as the home side again began to threaten, Bialkowski coming off his line quickly to head away in front of Assombalonga.
Forest were forced into a substitution in the 14th minute when Zach Clough took over
from Mustapha Carayol, who had suffered a knock.
Two minutes later, the home side were hit by a further double blow as Blackburn doubled their lead at Griffin Park and Birmingham went in front at Bristol City.
As the game approached the half-hour mark Town enjoyed a long spell of possession but without creating an opportunity before Forest’s danger man Assombalonga was twice found inside the area, Berra crowding him out the first time and Kenlock forcing him wide the second.
Forest created what was the best chance of the half up to that point in the 34th minute when Jamie Ward crossed from the left and Eric Lichaj got ahead of Kenlock but slammed over from a few yards out with the Town backline claiming he was offside.
It was Forest’s turn to appeal to the officials a minute later when Assombalonga claimed he’d been manhandled as Berra beat him to another Ward cross from the left.
The Blues came within an inch or so of going in front in the 37th minute when Rowe’s deflected shot fell to Samuel on the edge of the box. The on-loan Reading frontman hit a well-struck shot but Smith reacted superbly to tip a ball he had no right to save on to the bar.
Four minutes later, the home side took the lead from the penalty spot. A long throw from the right was sent in from the right, Bialkowski came to punch but was beaten to it by Jamie Ward, who hooked goalwards. Jordan Spence cleared off the line but referee Andy Davies pointed to his spot as the Blues keeper had collided with Ward having missed the ball. It looked a spotkick not too many officials would have given.
Assombalonga took the kick and smashed it into the roof of the net to transform the mood at a previously downcast City Ground. It was the former Peterborough striker’s 13th goal of the season and his third against Town.
Town weren’t far away from getting on terms in the remaining minutes of the half after Rowe won a corner on the right with a strong run. Huws sent over the flag-kick and Berra won it but failed to make enough contact with his header and the ball bounced wide.
Soon after, the whistle ended the half with Forest out of the relegation zone ahead of Blackburn on goals scored.
The scoreline was a touch harsh on Town who had ridden Forest’s early spell of pressure and had then been on top for long spells and but for Smith’s remarkable save from Samuel they would have been in front.
However, they were made to pay for poor defending - the throw which led to the rather soft penalty should never have been allowed to reach Ward - and the home side left the field at the break with the atmosphere around the City Ground far more positive and significantly less nervous than it had been minutes before.
Nottingham Forest: Smith, Lichaj, Mancienne, Mills, Cohen (c), Assombalonga, Osborn, Carayol, Ward, Vaughan, Worrall. Subs: Evtimov, Tshibola, Clough, Lam, Vellios, Cash, Brereton.
Town: Bialkowski, Spence, Chambers (c), Berra, Kenlock, Skuse, Huws, Ward, Sears, Samuel, Rowe. Subs: Gerken, Pitman, Webster, Dozzell, Moore, Emmanuel, Downes. Referee: Andy Davies (Hampshire).