THE reverberations that crashed out from this encounter could be felt as far away as Burnley, Plymouth and, even Southend.

If it wasn't a formality before, it is now. Sunderland are heading back to the Championship and there is nothing manager Mick McCarthy or chairman Bob Murray can do to stop it.

Even the greatest escapologist of all would struggle to pull off this impossible mission.

Had Sunderland's trip to Birmingham been recorded on the Richter scale before kick-off then it would have been a ten, such was the enormity of the occasion for both clubs.

With Birmingham third from bottom and the Black Cats cast adrift at the foot of the Premiership this was hailed as the occasion when something was going to give.

Either Sunderland would claw themselves closer to their opponents and towards the 19-point total they have set themselves, or the Blues would put a new ray of light into their survival fight.

Unfortunately for the club from Wearside it was the latter.

Birmingham have lost just one from their last five league matches and have extended the gap between themselves and Saturday's opponents to 13 points, a run never likely to be achieved by Sunderland.

In hindsight, for all their battling qualities and endeavour, Sunderland's squad does not possess the ability in abundance necessary to be able to preserve a place in the top tier of English football for more than a year.

With just 18 goals scored from 27 league matches it does not take Einstein to work out where things have gone wrong, while the 49 leaked at the other end suggests defensively they have hardly been Middlesbrough-like, never-mind Chelsea-like.

There remains a determination not to admit defeat, but even McCarthy is beginning to wane.

"Time and games are running out," he said.

"You keep going. I'm not going to con anybody and say mathematically impossible and all that rubbish.

"I can come out with that but it won't achieve anything.

"I understand the position and the implications for this football club but you still can't let it go. This club is a constant, the fans are, and you just keep going for the morale of me, the players and everybody connected with the club."

The displays of Rory Delap, making his first appearance since his January move from Southampton, and Stephen Elliott, returning after an injury lay-off, clearly improved morale after the restart.

But neither, nor any other player for that matter, could break down a Birmingham defence that Czech Republic centre-back Martin Latka, who spent time on trial with Middlesbrough earlier this year, marshalled well.

"At the moment I'm sat looking for silver linings on a very dark, poxy cloud," said McCarthy.

"The ones are Rory Delap, Grant Leadbitter - who I think's been excellent when he's played - and having Stephen and Kevin Kyle back. They are the plusses and that's it."

It was when Birmingham paid a visit to the Stadium of Light in late-November when it became apparent just how serious Sunderland's plight was. City nicked a late goal to win 1-0 and McCarthy was left to fume that most of his 'players wouldn't get into any other Premiership team'.

On the first half display on Saturday it was evidently clear why, although in fairness Birmingham's ineptitude was on equal footing.

A long-range volley from Kyle into Maik Taylor's arms and a sweetly struck left foot strike from Jiri Jarosik that flew wide was the best either side could muster, in one of the worst opening halves of top-flight football anyone will see this season.

But Birmingham gained the advantage six minutes before the break that they hardly deserved, a lead they managed to hold onto until the end.

After Nyron Nosworthy's block on Jarosik earned a free-kick, the dangerous Jermaine Pennant delivered a free-kick from wide on the left into the box. Danny Collins collided with Chris Sutton and Emile Heskey was able to guide his header into the roof of Kelvin Davis' net.

"I'm sure that there's contact but if Nyron was nicking Jarosik's wallet he'd have put up more of a fight and stayed on his feet," fumed McCarthy.

"But, like a few good other teams, there's not a great deal of difference between us and a lot of the strugglers - points there is, you can argue that, but in terms of playing and performances there isn't and they got the goal which was the only difference."

Things did improve after the restart.

Sunderland had a little more purpose with the strong wind behind them and Elliott's pace and Delap's drive instilling more impetus in the visitors' play.

But, despite this, Davis still had to make three fantastic saves from substitute Dudley Campbell, Heskey and David Dunn as Birmingham could have wrapped proceedings up.

Instead Birmingham had a nervy last ten minutes but Maik Taylor was never seriously tested and Sunderland were left with defeat number 21 from 27 Premiership matches.

The most painful thing of all for McCarthy and his men: There remains another 11 games before attentions can be turned to life back in the Football League again.