Gabbiadini rocketed home his 25th goal of the season from the penalty spot after Martin Hollund had brought down substitute Glenn Naylor.
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2.
When Peterborough's Edwards chased a bouncing ball back alongside Gabbiadini he appeared to bring the frontman down, but the referee was not impressed.
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3.
Naylor had only just come onto the field but found himself clean through after a three-man move involving fellow sub Lee Nogan and Gabbiadini.