Tranmere boosted their play-off hopes with a goal in each half at home to a battling yet limited Chesterfield side.
Visiting keeper Barry Roche brilliantly denied Chris Greenacre on 11 minutes but had no chance when John Mullin drove home after a defensive mistake.
Rovers dominated and Gareth Taylor and Ian Goodison missed headers to make it two and Shane Sherriff struck a post.
After Chesterfield's Colin Larkin hit the woodwork, Greenacre tapped in Chris Shuker's cross to seal the victory.
Tranmere: Ward, Stockdale, McCready, Goodison, Sherriff, Shuker, McLaren, Mullin (McAteer 51), Ellison (Davies 70), Taylor (Zola 74), Greenacre.
Subs Not Used: Hinchliffe, Tremarco.
Goals: Mullin 21, Greenacre 73.
Chesterfield: Roche, Bailey, Downes, Grimaldi, Picken, Allott, Hall, Holmes (Jackson 75), Meredith, Shaw, Larkin (Allison 67).
Subs Not Used: Jordan, Reuben Hazell, Reuben Hazell, Critchell.
Ref: G Sutton (Lincolnshire).