Nottingham Forest boss Stuart Pearce admits Birmingham City deserved their 2-1 win.
Birmingham had appeared to be heading for a 1-0 win following a fine first-half goal from Dave Cotterill, but the game exploded into life in the final 10 minutes.
Britt Assombalonga equalised from a close-range header in the 84th minute for his 13th goal of the season, but three minutes later the former Peterborough player pushed the ball over the bar with his arm following a corner.
Referee Geoff Eltringham awarded another corner despite protests from the Birmingham players. It was only when the fourth official, Nigel Smith, intervened that he changed his mind to award a spot-kick and send off Assombalonga.
In all the excitement Paul Caddis, who had missed his previous penalty at St Andrew's, coolly slotted away the match-winning penalty.
Pearce said: "I had mixed views at the time. It was well done to the officials for eventually getting the right decision. It was a big call.
"At the time, along with Birmingham's manager, Gary Rowett, I thought it was a handball. I was surprised the referee nor the linesperson, who was nearest, didn't pick it up at the time.
"Credit the fourth official. He saw it and put his neck on the block and made the decision on behalf of the three officials.
"The only question I asked the referee after the game was how he couldn't see the incident while the fourth official, who was five yards behind me, and myself both saw it as a hand ball.
"We will not go away and hide behind a disgruntled result. The officials got the decision correct and I will not bemoan that fact. Well done to them.
"We feel on the run of play we deserved at least to get a point out of the game but I cannot take any credit away from Birmingham's win.
"I am not going to moan about the decision. We have got to move on. We have been beaten and that hurts and it would be easy for the players and myself to hide behind the penalty decision."
