The significance of derbies to the balance of power in a city can serve to stifle and smother ambitions. Fear of defeat to rivals can outweigh the desire to beat them; a must-win game becomes a must-not-lose match. That, at least, was the approach Birmingham City took. Seventy minutes in, Aston Villa decided to risk defeat and were rewarded with victory.
Enter John Carew to augment Gabriel Agbonlahor in attack. That duo duly combined for the solitary goal in a weekend where the eight previous Premier League games contained an average of four apiece. Even one appeared unrealistic at St Andrew's during a lengthy impasse. Both sides deployed a 4-5-1 formation; Villa's, at least, is designed to aid counter-attacking. Birmingham's is essentially cautious.
Yet it produced a common problem in these parts. Congestion is experienced all too often on the M6, the M5, the M40 and the M42 in the West Midlands. With 10 men in midfield, parts of the St Andrew's pitch were similarly crowded. Then Martin O'Neill navigated his way out of the gridlock, enabling Villa to take the aerial route to Carew.
Indeed, the Norwegian beat Roger Johnson, a fine header himself, in the air to Ashley Young's free kick, sending it back across goal. There Agbonlahor eluded his marked to head in his 85th-minute winner.
"We are able to adjust and adapt," said O'Neill. "It looked as though it was heading for stalemate and I wanted us to force more pressure on Birmingham if it was possible. We got John on and he made a big contribution."
O'Neill was too diplomatic to draw a contrast, but his Birmingham counterpart did. "I felt that Villa's power in midfield could over-run us," said Alex McLeish, explaining his side's shape. "They did the same at Anfield and played the same at home [against Fulham] with one striker, so I don't see why I can't use one striker at home. I thought the tactics were spot on."
Others might not concur. McLeish is a manager who has spoken of the importance of winning home games, a failing of Birmingham's when they were relegated two seasons ago. Yet too little ambition was apparent to prevail in this one. The initial formation remained intact until the closing minutes: when Cristian Benitez, who is rapidly becoming Birmingham's specialist substitute, came on, it was at the expense of the lone striker, Garry O'Connor.
Negativity spread from McLeish's tactics to his post-match interview. "The difference between us and Villa in financial clout and quality is a gulf, but it didn't look like that today," he insisted. However, his side had become more defensive at half-time when a thigh injury forced the removal of James McFadden. Lee Carsley replaced him, becoming one of five essentially destructive central midfielders scattered around the Blues side at the same time.
"It's a harsh result, there's no doubt about that," added the Birmingham manager. In some respects it was - for much of the game neither side merited a win - yet in others, Villa's more progressive attitude made them deserving victors.
At Birmingham, the emphasis is on the defensive. McLeish's safety-first theories served Scotland well, and plenty north of the border could be forgiven for feeling nostalgic about his brief but successful stint in charge of the national team. He earned Birmingham promotion despite scoring fewer goals than relegated Norwich and it is not hard to see why their first five Premier League games have only produced six goals. Birmingham have only managed two of them.
This presented an opportunity to increase that meagre tally. Villa fielded a trio of debutant defenders, in Richard Dunne, James Collins and Stephen Warnock, and recorded a clean sheet. Allegiances to these two clubs don't always last long.
It was a tale of one city, but of two Brummies. Agbonlahor, the resident Villa fan, endured some unpleasant chants about his mother before answering his tormentors among the Birmingham support with the winning goal. The City club captain, Carsley, is a lifelong fan who was attending his first derby in any capacity. Dropped to the bench, he attempted a couple of audacious shots before local hero status was claimed by Agbonlahor and he was sacrificed in the search for an equaliser. The substitute was substituted, always an ignominious exit, a couple of minutes after Agbonlahor celebrated.
His fellow Villa supporters were as ecstatic as Agbonlahor, the other Bluenoses as despondent as Carsley.
MAN OF THE MATCH: Richard Dunne - This was an accomplished debut for the former Manchester City captain and an auspicious start for his new-look central defensive partnership with the equally impressive James Collins. Both were reassuringly solid.
BIRMINGHAM VERDICT: An injury crisis has been the backdrop to their season and McLeish could benefit from seeing more of his defenders and forwards fit again. A decent defensive record shows the stand-ins at the back have fared well, yet a side with such limited intent surely need to commit more players forward if they want to win games.
ASTON VILLA VERDICT: The 4-5-1 formation is serving Villa well, but Carew has a habit of making an impact and for games such as Portsmouth's visit on Saturday, there is certainly a case to revert to 4-4-2 and give the Norwegian a start.
THE LIFE OF WILEY: Alan Wiley, one of the Premier League's better referees, was in the crowd. If the match provided little excitement, he may have had the consolation of watching an excellent display by Howard Webb, the official on the pitch.