Defender Shaun Barker headed the winner in the final minute as Blackpool stunned Crewe, despite having Simon Gillet sent off 11 minutes from time.
Andy Morrell put the visitors ahead early on when he fired in a long-range strike but The Alex equalised when Nicky Maynard volleyed in.
When Gillett was sent off after picking up a second booking it looked as though the Seasiders would do well to draw.
But Barker headed home Keigan Parker's free-kick to earn an unlikely win.
Crewe: Williams, Otsemobor, Baudet, Cox, Taylor, Rix, Osbourne, Vaughan, Varney, Maynard, Jack (Higdon 78). Subs Not Used: Tomlinson, Lowe, Flynn, O'Donnell.
Goals: Maynard 67.
Blackpool: Evans, Barker, Jackson, Evatt, Dickinson, Fox (Jorgensen 78), Southern, Hoolahan, Gillett, Vernon (Blinkhorn 90), Morrell (Parker 85).
Subs Not Used: Jones, Joseph.
Sent Off: Gillett (79).
Booked: Southern, Gillett.
Goals: Morrell 3, Barker 90.
Ref: C Boyeson (E Yorkshire).