Carl Heeley and Matt Gardiner made several changes for this Vanarama National League North match but a defensive mistake in each half sealed City's third defeat in a row and the fourth of the new season.
Danny Jackman came in to make his first start to a game with Sam Minihan, Kieran Morris and Ryan Rowe also starting. George Nash and Jamie Spencer dropped to the bench with Connor Gater. City naming just four subs with Daniel Lloyd-Weston as replacement keeper. Clayton McDonald missed out.
Glenn Walkers cross after 7 minutes gave Brackley an early chance but Steve Diggin's header was blocked by Alex Gudger.
Sean Geddes showed a bit of his unique talent, slipping but managing to control a long ball from Tyler Weir on his chest, before unleashing a shot which Brackley cleared for a corner.
Ryan Rowe was substituted on 19 minutes with a dead leg, being replaced by Jamie Spencer.
On 27 minutes Brackley got the break, coming from a give away by City. Kieran Morris, with plenty of time opted to play out to Sam Minihan on the right, who was quickly charged down and his resulting pass back to Morris saw Steve Diggin nip in. The ball fell kindly for Brackley but there was no argument about the finish, as Diggin curled the ball in from outside the box, giving Nathan Vaughan no chance.
Daniel Nti's free kick on 34 minutes went over the bar, then two minutes later, good work from Sean Geddes released Tyler Weir, whose ferocious drive from 25 yards again went over the bar.
City once again had plenty of possession but could not find a way to test Dan Crane and the second half continued much the same as the first.
On 64 minutes Brackley doubled their lead after forcing a corner. Glenn Walker's in swinger was missed by Nathan Vaughan and Pablo Mills had an easy un contested header past the City defence.
Sean Geddes's strike in the 87 minute was tipped over by Crane and City forced several quick corners to end the game.
A bonus for City was that 11 players finished the game with just Alex Gudger picking up a yellow card.
Att: 273