Early goals from Ashley Nadesan and Tom Nichols gave the Reds a 2-0 lead inside a quarter-of-an-hour.
Jordan Bowery then pulled a goal back from the penalty spot before George Lapslie levelled for the Stags on 27 minutes.
Nadesan hit what proved to be Crawley’s winner on 46 minutes, to move the Reds three points clear of the drop.
Here’s how reporter Jordan Grainger rated the Crawley Town players against Mansfield Town.
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