Although Brian Barry-Murphy's youngsters were eventually edged out by our League Two opponents, the two sides served up an absolute thriller at the One Call Stadium.
Mansfield forward Lukas Akins headed home the opener from a corner inside 17 minutes after Dire Mebude had seen an earlier effort cleared off the line.
City responded defiantly with a quick double before the break - both thanks to incisive balls over the hosts' defence from goalkeeper Mikki van Sas.
But the Stags would eventually turn the game on its head - pulling level early in the second half through an acrobatic finish from James Gayle.
And the turnaround was completed late on when George Lapslie slid home at the near post to hand Mansfield the points.
There was still time for one last chance for City though, as Borges' vicious effort came crashing back off the bar from the edge of the box.
Relive an exciting encounter via the video above...
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