While the tactic proved mostly effective, it was City who capitalised on a minor mistake at the back by Athletic when Jordan Joblin-Hall latched on to a wayward clearance and put the ball past Athletic's keeper, giving City a 1-0 advantage.
As time marched on towards the half-time break, play continued to be open and attacking, with both sides having opportunities to claim goals, only for the opposition defence to break up the attacks.
City coach Kelvin Francis commented on his frustration at watching how the game unfolded from his perspective.
"We just weren't fluid enough. It was always going to be hard pulling together a squad from three different teams, each with their own differing playing philosophies, and getting them to gel quickly for this match.
"I felt we had more of the possession, but Athletic played quite defensively when they turned over the ball.
"The dropped back behind the ball, and we found it really hard to break them down."
The second half was much the same as the first, with neither side able to gain the advantage, the midfield of both teams counteracting the other and forced each to use the width of the park as best they could.
With time ticking away, the game burst into life with Athletic finding the back of the net with 15 minutes to go.
After winning a corner, Athletic's Matthew Hausman delivered a ball toward the centre of the box, which found the feet of Richard Saunders, after taking a deflection from Symon King, allowing him to bury the ball and level the scores.
The intensity step up was evident. Both sides were tired but found a little extra in the derby match, and looked to press for the next goal.
The pressure was sure to make someone crack at some point and it was City who managed to find the chink in the armour of the Athletic defence after a momentary lapse of judgement.
Adrian Ngaau intercepted a clearance on halfway, combined with teammates, before receiving the ball back and placing it into the net to give City the victory and a crucial second away goal with just two minutes left to play.
The second leg is this weekend, with City the hosts.