A Darryn Stamp header, 20 minutes from time was enough to see Gainsborough advanced to the next round of the FA Trophy.
The veteran centre forward latched onto a Ciaran Toner free-kick to power Gainsborough into Monday’s draw at the expense of Brackley.
It was, for the majority, a dominant performance from the men in Blue as they played some terrific stuff.
Quick and slick interchange was the motto of the day, as they ran the Saints ragged at times, particularly in the first half.
The fluid performance took its toll on the visitors after five minutes.
Danny Forrest, a new singing from Guiseley making his home debut, poked the ball home following a Tom Davie header.
The former Bradford City player reacted sharply to pounce on the rebound.
Trinity began advancing through the gears after this and their expansive play was a joy to watch.
The only problem was that they could not get the ball over the line once more.
The latter stages of the half saw efforts from Davie, Liam Davis and Ciaran Toner but despite a shaky start, Brackley keeper Dean Snedker was making some smart saves.
As luck would have it, the visitors regrouped at half time and within seven minutes they were level.
Will Green controlled a cross from the left on his chest before smartly finishing.
It was the only time throughout the 90 minutes where Brackley looked dangerous, as moments later they threatened the Blues goal once more.
Trinity seemed a smidgen bamboozled by this.
Not before long they settled and began about trying to win the game.
It was a Toner free-kick which inspired the match winner.
The Northern Irishman bent a wonderful delivery around the Brackley defence for Stamp to head home his third of the season.
Manager Steve Housham admitted after the game that Trinity should have retained the ball better and taken their chances.
He said:“We were sloppy in the first half, we gave the ball away cheaply.”
“I said to them at half-time that the only team that is going to beat you is ourselves.”
“We kept it well in a lot of spells but there times when we gave the ball away easily.”
“First half we should have been out of sight, we played some great stuff but we were not ruthless enough.”
“Second half, we just didn’t start right.”
“They got a goal they probably deserved but the old man stood up again and got us through.”
Trinity will find out their fate on Monday lunchtime but the club’s next focus is dealing with league leaders Barrow on Saturday.
Gainsborough Trinity: Budtz, Roma ©, Quinn, Picton, Davie, Roberts, Binns, Toner, Davis, Stamp, Forrest. Subs (not used): Lacey, Salt, Karkach, Wisdom-Lockwood, Emery.
Brackley Town: Snedker, Samuels, Carruthers, Ed Odhiambo, Sharpe, Austin, Addy-Nelson, Whittall, Rowe, Green, Built. Subs (not used): Curtis, Kaziboni, Er Odhiambo, Waldon, Pearson.
Goalscorers: Forrest (6), Stamp (69); Green (52).
Referee: Mr P. Graham.
Assistants: Mr M. Rawcliffe, Mr P. Sporne.