After a couple of early corners won by Ellington, Celtic's first real chance came from an excellent first time cross off Black that Hume headed just over the bar. There was some great interlinking play from the Celtic midfield, which put the Gainsborough defence under a great deal of pressure but the telling ball just would not come.
A clash of heads between Parr and Maxfield left Maxfield on the floor, but play went on, and Anson profited with space to make Pettinger pull of an excellent save. Bird should have put the visitors into the lead after Thorpe lifted the ball to the back post, and though he was under pressure from Keeling, Bird was inside the six yard box and cleared the stand behind the goal with his shot.
Celtic continued probing and pushing at the Gainsborough back line, with a Black cross almost causing Pell to head into his own net, the looping header going narrowly wide with Sollitt rooted. From the corner, Trinity cleared and raced up field, forcing Sykes into a timely challenge to stop Bird. The ball fell to Graves but his hurried shot was watched all the way by Pettinger. Brodie's last act of the game was to put a superb through ball into Hume's feet at the edge of the six yard box, he drew defenders like a magnet and slid the ball out to Morris who was racing in, Morris smacked his shot across Sollitt and into the back of the net.
At the start of the second half, Bird missed another sitter as Jamie Smith put the ball through the six yard box; Bird slid in at the back post, and diverted the ball wide. Gainsborough were getting hold of the game, and looking increasingly threatening as Celtic sat deeper and deeper. A Purkiss corner was cleared back to the fullback, who lobbed it to the back post, and Parker's free header was over the bar.
Whether Pettinger meant it or not, a long punt down field was heading towards the top corner of his opposite number's goal, until Pell nodded it wide. The corner came back to Ben Smith (on for Brodie), and he found Hume who forced Sollitt into a good, but unnecessary save as Hume was called incorrectly offside.
It didn't matter as seconds later and Maxfield lofted the ball to Hume who controlled superbly, before putting the ball into Winn's path. Winn controlled it on the run and smashed it past Sollitt to double Celtic's lead. The Trinity players were incensed as they felt Winn had handled to control, but he hadn't and the goal stood.
With twenty minutes remaining Black looked to have won the ball in his challenge with Graves, the referee saw it differently and booked Black, awarding a free kick that Bird put into the back post for Parker, but his excellent header was met by an equally excellent save from Pettinger. A loose ball from Ben Smith allowed Graves to steal the ball and race towards goal. Sykes almost got back, and Pettinger almost reached the shot, but neither did and Graves reduced the arrears to set up a grandstand finish.
Though Gainsborough got a succession of free kicks and corners, the balls into the box were mere catching practice for Pettinger and Celtic held firm to go through to the first round proper and a home tie against second placed Hinckley United.