But Bruce must have been as surprised as anyone with the ease of their win over Villa - who have yet to beat their local rivals in the Premiership.
The 101st game between these two clubs was a game of contrasts with Villa's usually secure defence having a nightmare and Birmingham's goal-shy attack finally finding the target.
As a result Villa slumped to their first home defeat of the season as form, as usual, went out of the window.
Villa boss, David O'Leary, had his programme notes rewritten and he must have wished he could have rewritten the script for this game as it was a calamitous performance from his side.
Birmingham manoeuvred themselves into a winning position as a result of an outstanding first half display, with goals from Clinton Morrison and David Dunn before Gareth Barry notched Villa's goal in injury time.
Battling Birmingham made a flying start but in view of their goalscoring problems it was nevertheless a major surprise when Morrison gave them a shock eighth-minute lead following a series of mistakes by Villa's defenders.
Olof Mellberg failed to put in a positive tackle on Emile Heskey who was able to head the ball forward. There was still no apparent danger as Morrison moved onto the ball which he hit first time through the legs of Mark Delaney.
The shot lacked power but Thomas Sorsensen misjudged the bounce and the ball flicked his shoulder and deflected embarrassingly into the net.
Villa attempted to redeem themselves but their plight took a turn for the worse when a confident Birmingham increased their lead in the 18th minute with a well executed and simple goal that knocked a lot of fight out of the home side.
Morrison set up Damien Johnson on the right and his low cross into the middle was coolly tapped home from close range by David Dunn.
At this stage the home defence was all at sea against the vibrant Blues.
Dunn skipped through again and only a brave diving save by Sorensen prevented another goal.
Dunn, enjoying his best game for Birmingham, revelled in the situation as he repeatedly ghosted through Villa's defence. The former Blackburn player produced a cracking cross-shot which beat the unguarded Sorensen only for the ball to go screaming wide of the far post.
The game erupted into in the 37th minute when Johnson kicked out at Barry. A group of players were involved in the scuffle with Johnson and Mellberg, who had raced fully 40 yards to the incident, both being booked.
Mellberg had a most frustrating first half and just before the break he again failed to cut out Heskey who saw his angled shot from the left hit the far post as Villa were completely perplexed.
There was a more positive start from Villa in the second half with Carlton Cole producing their first shot on target in the 46th minute and Barry having a goal disallowed for offside.
Unlike in many recent games Birmingham's play did not come adrift in the second period and City held on to score a memorable, and vital, win.