The multi-millionaire owner of the Molineux club demonstrated the unity Wolves will need to survive this season after his employees on the pitch had rallied around to secure three points the importance of which cannot be overstated.
Make no mistake, this was a hugely significant victory for the Black Country team. Defeat yesterday would have left them nine points behind Alex McLeish's side. Nursing a lengthy injury list, McCarthy must have wondered where the quality was to overturn a Birmingham side on the back of a four-match unbeaten run.
You beauty: Stephen Hunt (right) celebrates his goal with team-mates Stephen Ward and David Edwards
But necessity is the mother of invention and, with several players deployed out of position, basic virtues of hunger and work rate proved beyond the visitors whose display, for the first hour at least, bordered on hapless.
Stephen Hunt's near-post finish on the stroke of half-time ultimately divided these two but the reality was that the makeshift 11 thrown together by McCarthy should have enjoyed a far healthier return.
And while the show from Morgan was unusual and welcome for the watching public, it wasn't to the home boss who said there has never been anything other than unwavering support from those above him.
'Steve cares about it, ' said McCarthy. 'He's very supportive and it's been great.
'I'm not that surprised at the gesture. He's feeling it like the rest of us. We are in the bottom three and not getting results.
'I guess what is nice is that he comes down and everyone sees it. I know it is there all of the time. I don't need him to do that to have that nice feeling of support. I have it from (chief executive) Jez Moxey and him anyway. It's great."
Led by Sylvan Ebanks-Blake in the absence of Kevin Doyle, the former Manchester United trainee perhaps enjoyed his finest hour in an Old Gold shirt for some time.
His effort has sometimes been questioned but he made McLeish's highly-regarded defensive duo of Roger Johnson and Scott Dann uncomfortable throughout.
Birmingham goalkeeper Ben Foster had already denied him twice before the winning goal. A long ball from Wayne Hennessey was flicked on by Dave Edwards. Ebanks-Blake turned Dann before supplying a cross that was neatly tucked away by Hunt on the half volley.
Despite chopping and changing his team there was little response from the visitors until the final quarter.
Wolves, desperate to cling to their lead, suddenly became nervous with the finishing line in sight.
CameronJerome almost reached the end of a Jean Beausejour cross before theSouth Bank enjoyed the rare sight of Kevin Phillips sending a headerwide. The former Villa and West Bromwich old boy has turned scoringagainst Wolves into an art form. But not this time as the hosts kepttheir first clean sheet of the season.
Itwould have been a huge injustice had Wolves not scraped home given theoverall balance of play. Birmingham were dreadful - although McLeishknows that laying into his players for one below-par performance wouldbe counter productive.
Crucial moment: Hunt fires home for Wolves
Their afternoon began poorly with Johnson picking up the fastest booking of the season so far - after just 75 seconds - and it didn't improve much thereafter. Of course, statistics can be misleading.
This was only the Blues' second defeat in 11. However they have not now won away from St Andrews since defeating Portsmouth nine months ago and two wins in 15 is worrying form.
'We never really got started until the substitutes came on,' said McLeish, 'but you have to give credit to Wolves. They lost some key players today and maybe that brought some complacency - psychologically - in our ranks.
'Mick must have got an extra 10 percent off every single player today. Several of them played out of theirskins. This was just a poor performance. It was uncharacteristic. Wejust left our tools at home today. But at the same time I did say tothe players that Wolves really had a cause today, the fact they're inthe bottom three is one and then losing those big players.'
Battle: Birmingham's Cameron Jerome clashes with Richard Stearman at Molineux
McLeish played down Foster's heroics in goal for Birmingham, which was surprising given the quality of his stops.
'He made some saves, I need to have a look at how brilliant they were. I thought there were a lot of routine saves there,' McLeish added.
McCarthy responded: 'He's a very good keeper and if they're routine then fabulous, but he kept them out of the net whether they're routine or great saves. Wayne hasn't even made one routine save.'
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