Two second-half goals in quick succession from Ben Close and Kyle Hurst were enough to hand Doncaster a much-needed boost after Tranmere had earlier hit the woodwork through Ethan Bristow.
Visitors Tranmere created the best chances to score prior to the goal and also went close through captain Kane Hemmings, who was denied by Jonathan Mitchell from close range.
But a slice of luck saw Close break the deadlock when his deflected effort from outside the box flew over Mateusz Hewelt and into the back of the net on 62 minutes.
Three minutes later Kyle Hurst grabbed his seventh goal of the season with a well-taken finish after Charlie Lakin played him through one-on-one.
Brad Walker hit the bar in response for Tranmere but Doncaster held out comfortably to earn just their fifth clean sheet in League Two this term.
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5. Tom Anderson - 7
Made some important clearances throughout during a solid display. Photo: HOWARD ROE, Howard Roe/AHPIX LTD
6. Ro-Shaun Williams - 7
Another solid performer but might have tried his luck with a shot when space presented itself for him in Tranmere's half in the first period. Photo: Howard Roe/AHPIX LTD
7. Tommy Rowe - 7
A competent display on the left of a back three. Subbed after getting injured following a collision with Jonathan Mitchell as they both tried to clear the ball. Photo: Andrew Roe/AHPIX LTD
8. Ben Close - 7
Kept possession ticking over in the middle and opened the scoring with a deflected strike. That proved to be the turning point in the match. Photo: Howard Roe/AHPIX LTD