Birmingham boss Steve Bruce singled out DJ Campbell for praise after his two-goal show against Coventry.
Campbell was a late inclusion in the squad for the 3-0 win over Coventry after new signing Andy Cole was forced to pull out with a hamstring injury.
The former Brentford striker made the most of his opportunity by coming off the bench to score twice to fire Birmingham back into the automatic play-off spots.
Bruce admitted he made a mistake by leaving Campbell out of his original squad and praised him for the attitude he has to the game.
"I made a big mistake by leaving him out of the 16 and I had to admit that to him and apologise to him for that," Bruce said.
"He has brightened up training sessions since he came to the club. He's absolutely delighted to be a footballer instead of driving a van.
"He keeps knocking on the door and I'm obviously going to have to put him right in my thoughts again.
"It's unfair to label him as a super-sub, but he is very, very bright. Some people are poor when they come on and can't adjust to the pace of the game. DJ isn't like that, though. He's bright and he's lively and after the chances we missed in the first half it was great to see him get a chance and put it away with his first touch."
Bruce was also happy with the performance of his side as they easily swept aside the challenge of Coventry.
"I saw Coventry slaughter Barnsley a couple of weeks ago and I knew it was going to be a tough game, but in the end we made it very, very comfortable. More comfortable than I thought it was going to be at the start if I'm honest.
"It was pretty convincing. It could have been all over in the first half with the chances we had, but that has been a bit of an Achilles heel for us. I thought if we could get the second one we could run away with it and in the end it turned out to be very convincing and very comfortable."
Coventry manager Iain Dowie has challenged his side to bounce back from the defeat and produce a good end to the campaign after he suffered his first loss in charge of the Sky Blues.
"We have to put it right because I want a big finish to the season," Dowie said.
"I want us to put a real run together and I want us to be among the top two or three form sides in the division come the end. We were top of the form table before today's game and we want to make sure we get back up there."