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.
1. Crawley Town player ratings v Mansfield Town
The Crawley Town player ratings from Saturday's win over Mansfield Town Photo: Cory Pickford
2. David Robson - 7
Only his second league start for Crawley, and he will be very frustrated with the two goals he conceded – through no fault of his own. Other than that, he looked fairly solid coming off his line quickly and keeping Mansfield Town out for the most part. Photo: Chris Holloway/The Bigger Picture.media
3. Travis Johnson - 6
Johnson had a solid game overall but much like the rest of the defence let his head drop following the two Mansfield goals. Reckless at times after those goals went in leading to him seeing yellow and needing to be taken off. Subbed off for Teddy Jenks. Photo: Cory Pickford
4. Dion Conroy - 7
At times in the first half didn’t look on top of his game but was great in the second half. One of the main reasons that Mansfield failed to break down the reds in the second half so manager Lewis Young will be pleased. Photo: Crawley Town FC