Two late goals brought a 14th home victory for Tranmere and extended their unbeaten run to 14 matches.
A bumper crowd of 10,418 watched the match with the spectators allowed in free after Saturday's match was abandoned at half time because of the climbing antics of a fan.
The Merseysiders could easily have had three goals inside the first three minutes but Kevin Pilkington in the Mansfield goal made fine saves from Iain Hume, Simon Haworth and Gary Jones.
But Pilkington was left stranded when Jones fired home a left-footed shot in the 14th minute from a Gareth Roberts cross after Mansfield had given away possession.
Tranmere dominated the game but were rocked in the 53rd minute when Mansfield were awarded a penalty for a push by Ian Sharps on Jake Buxton after a corner.
Liam Lawrence, who was outstanding for Mansfield, netted from the spot with a shot into the left-hand corner which keeper John Achterberg reached but could not keep out.
Tranmere regained the lead in the 80th minute when Simon Haworth headed in his 20th goal of the season from a cross by Roberts.
Substitute Jason Price settled it, netting at the second attempt following a breakaway in the second minute of injury time.
Tranmere just missed out on the play-offs as Mansfield head out of the division at the wrong end of the table.
Rovers boss Ray Mathias said after the match: "We ended our home programme on a high.
"We took our foot off the pedal at half time and got punished but we kick-started again after sending on two substitutes.
"Their keeper made some excellent saves. They put five across the middle and made it difficult for us but we got there in the end." Mansfield assistant manager John Gannon commented: "We showed commendable spirit but it was not enough." Haworth's goal brought his tally for the season to 20 and he said: "I was gutted to have Saturday's goal ruled out through the abandonment but it was great to get three tonight.
"There was nothing to play for really but we scored a few goals to thank the fans. We have done our best for them but have just missed out on the play-offs."