After going in 1-0 down at the break, they turned the match around with new signing Corey Whitely and Luke Coulson both scoring, writes Tom Feaheny.
This means the side are now on 49 points and only three from the play-off places.
“The second-half performance in particular was terrific from us, “I thought we lacked quality in the first-half with the ball but in terms of defending," McMahon told the club's website.
"They put us under real pressure. And in that first 20 minutes I thought we defended our box and our goal ever so well.
“We had a couple of counters ourselves that we couldn’t capitalise on but we lacked a little quality in the final third in the first half and we changed it in the second."
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