In warm sunshine, the sides had battled out an unexciting first half with Harry Pell missing the best chance for the visitors.
But, after Mitch Rose had notched his second goal of the week four minutes into the second-half, the visitors threatened rarely and Mansfield must have thought they were about to win their first home game to build on that opening victory at Newport.
But it wasn’t to be as O’Shaughessy smashed in the sort of goal more regularly seen on Match of the Day to spoil Stags’ day.
The leveller rocked the Stags who were lucky not to then lose it as the visitors produced a grandstand finish.
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