Stags were 2-0 ahead and well on top, but Ali Koiki's 61st minute reply has give the Cobblers heart and they dominated the rest of the game, forcing Stags to defend stoutly.
“We definitely felt were in the ascendancy in the second half and we're going to make sure we take that momentum into the next game,” said Brady.
“We showed character and spirit to come back into the game second half and I thought we acquitted ourselves well in that second half.
“At half-time we told them there were certain things we'd done all season that we weren't doing, and we looked a lot more purposeful and aggressive in our play.
“Credit to Mansfield. It was a strong game tonight.
“We are now looking forward to taking them back to Sixfields. We have been strong at home all season.
“We did come back to 2-1 but we know we still have a lot to do.
“But we know what we can do.”
Northampton could have had their chins on the floor after missing out on promotion on the last day, but instead showed true grit.
“I know within what they are capable of and one thing is we have never laid down all season,” said Brady.
“We have come back when we have had setbacks and we are probably at our best when our backs are against the wall. We come out fighting and we get results.”