Substitute Freddy Eastwood scored an injury time winner to make it four games unbeaten for in League 2, as Blues won 1-0 at Burton Albion.
Eastwood came off the bench to fire a late winner against ten-man Albion after Billy Kee had been sent off just before half-time.
The hosts had a chance of their own before Eastwood’s goal, but substitute Matty Palmer saw his shot come back off the post.
Rob Kiernan made his debut for Blues in place of the suspended Luke Prosser, while Ryan Leonard, Will Atkinson, Daniel Bentley, Barry Corr and Cauley Woodrow were all back in the side after Tuesday’s Johnstone’s Paint Trophy defeat to Dagenham & Redbridge.
Kiernan was immediately in the action as he followed Billy Kee into the referee’s book for kicking the ball away with just a couple of minutes gone.
Ian Sharps had the first real chance of the game, but his volley from 20 yards went just wide of Daniel Bentley’s post.
Kevan Hurst had a half-chance for Blues moments later, but fired wide of the target, before Bentley held Adam McGurk’s curling effort.
Blues’ first real chance came just after the half-hour mark. Kevan Hurst’s free-kick was headed towards his own goal by Sharps, but Jordan Pickford got down to make a good save.
The tackles had been flying in all afternoon, and just before the half-time break, Burton were reduced to ten men. Already booked, Kee flew in to a tackle on Ben Coker and left the referee with no option but to show him a second yellow.
With the man advantage, Blues began the second-half well on top, but were unable to find a way past a resilient Burton defence.
Burton had rarely threatened, but almost found a way through in the 78th minute. Robbie Weir’s ball in found MacDonald, but he headed just wide of Bentley’s goal.
Substitute Freddy Eastwood worked himself a shooting opportunity a couple of minutes later, but his shot went well wide from 20-yards.
With Blues pushing for a winner, Burton almost snatched it themselves. Palmer ran from his own half before seeing his shot come back off the post.
It looked as though Blues would be left frustrated, but Eastwood’s deflected volley in injury time cannoned in off the post to hand Blues all three points.
Blues: Bentley; White, Phillips, Kiernan (Straker), Coker; Clifford (Payne), Atkinson, Leonard (Eastwood); Hurst, Woodrow, Corr.
Subs not used: Smith, Auger, Reid, Timlin