Doncaster became the first visiting team to win a League One match at Chesterfield since August, when Jason Price punished a mistake by Barry Roche to settle an open and hard-fought local derby.
Roche failed to get any distance on his attempted punch in the 14th minute and Price lobbed the ball into an empty net from 12 yards.
That was enough to give Doncaster back-to-back victories and ease their relegation worries, while Chesterfield have now lost their last two matches.
The home side had plenty of possession but the finishing did not match the approach work and Doncaster keeper Alan Blayney was only seriously troubled on a couple of occasions.
He had to react sharply to keep out a low shot from Jamie O'Hara 30 seconds into the game and needed to tip over an overhead kick by Colin Larkin in the 49th minute.
Doncaster always looked threatening on the break and would have won more comfortably but for a penalty miss by skipper Michael McIndoe that put extra pressure on the defence.
But a composed performance by Kevin Horlock just in front of the back four added some substance to the Doncaster side.
Chesterfield will feel they had enough of the ball to have taken something from the match and on another night, Larkin would have had some reward for his tireless running and persistence.
He came close to equalising with a 27th-minute shot that went just wide of Blayney's right-hand post and his acrobatic bicycle kick four minutes into the second half almost caught the keeper out.
Kevan Hurst almost surprised Blayney with a snap-shot to the near post but Doncaster also had chances, with Price heading wide from 10 yards in the 57th minute.
They should have scored again when Paul Green was brought down by Aaron Downes but Roche guessed the right way to go and clawed McIndoe's low spot-kick to safety.
Ross McCormack also should have scored four minutes later when Leo Fortune-West sent him clear, but he shot wide and those misses could have proved costly.
With 12 minutes to go Larkin turned sharply but his low left-foot drive from 12 yards lacked accuracy and the ball flashed across the face of goal and out of danger.
Doncaster played out the remaining minutes without too many alarms while Chesterfield suffered another setback when experienced striker Wayne Allison was substituted with a hamstring problem.
