Luke Murphy's stunning volley secured the vital point after Harry Davis' own goal looked set to deny Crewe a shot at League One.
In the end, local rivals Port Vale gave them a helping hand by beating Oxford at home.
Davis said: "We knew at half-time that Vale were winning but we just wanted to do it for ourselves, we didn't want to rely on them down the road.
"In August, we were bottom and we've got to the play-offs so I can't be too fussy about who we play, we are happy just to be there and we have improved no end."
