Debutant Federico Macheda stabbed home an injury-time equaliser to earn a morale-boosting point for Clark's struggling side, who featured five debutants in total as off-field problems continue to affect matters on the pitch.
Steve McClaren's Derby had been vastly superior for the most part, despite going behind to Brian Howard's 48th-minute header. The Rams levelled through Patrick Bamford and had a two-goal lead thanks to Chris Martin and Craig Forsyth's goals.
However, Chris Burke's 78th-minute strike kept City in touch before fellow substitute Macheda, signed on loan from Manchester United late on Friday, stabbed home an unlikely leveller.
"I've just said to them that if they give me that from now until the end of the season we'll get lots of positive results," said Clark, who is operating on a shoe-string budget while the club continues to struggle in the face of owner Carson Yeung's legal problems.
"The desire and never-say-die attitude was there for everyone to see. We could have buckled at 3-1 down against quality opposition but we kept going and got a terrific ending to the game.
"It's a very, very young team full of people who have just got to know each other within a couple of days with so many debuts being made.
"The lack of experience is scary at times but they're taking it in their stride and showing a mental courage to keep fighting and fighting.
"Federico didn't meet his team-mates until 12.30pm today so that's probably why he started on the bench. But he made a huge contribution and looked bright."
Former England boss McClaren was left to bemoan his side's naivety.
"We should have won it easily and instead we ended up drawing, so that's a disappointment," he said. "It's a harsh lesson for our team.
"At 3-1 we lost our discipline and didn't control the game. We just went for it and a game we could have won 4-1, 5-1 or 6-1 ended up a 3-3 draw.
"The second goal we conceded was an absolute disgrace. It was a terrible goal. When we lost possession we had six players in front of the ball, Lee Grant saved from Macheda but we failed to defend the loose ball and Burke scores.
"It's cost us, we've missed a great opportunity in a game we should have won but that's football."
Derby would have led at the break had Craig Bryson not missed a penalty late in the first half.
Howard nodded the hosts ahead before Bamford hammered in the equaliser after hitting the woodwork in a fraught opening to the second half.
Derby's quality told as Martin put them ahead with a deflected long-range effort and the game seemed beyond Birmingham when Forsyth coolly slotted in a third.
Yet City, without a win at home since October 1, refused to give in as substitute Burke curled home after Macheda wasted a one-on-one.
Their rewards came deep into added time as on-loan midfielder Emyr Huws flicked a corner against the post before fellow newcomer Macheda reacted to fire home a dramatic leveller.