Chesterfield swept aside Port Vale to ease their relegation worries. A first-half strike from Phil Picken deservedly gave Chesterfield the advantage after an error by Joe Anyon in the Port Vale goal.
But goalkeeper Aynon could do nothing about the second which Ward blasted home with 11 minutes left.
Wayne Allison struck in stoppage time from an acute angle while Vale failed to force a save out of home goalkeeper Barry Roche until injury time.
Chesterfield: Roche, Bailey, Picken, Downes, Grimaldi, Niven, Allott, Hall, Holmes (Davies 90), Allison, Ward (Larkin 80).
Subs Not Used: Jordan, Hazell, Shaw.
Booked: Ward, Bailey.
Goals: Picken 38, Ward 79, Allison 90.
Port Vale: Anyon, Pilkington, Walsh (Abbey 46), Fortune, Weston, Sonner, Whitaker, Gardner (Cardle 66), Kamara (Husbands 74), Constantine, Sodje.
Subs Not Used: Musselwhite, Hulbert.
Booked: Gardner.
Att: 3,752
Ref: M Pike (Cumbria).