Lucas Akins scored twice and Louis Reed and George Maris also netted for the visitors, with Levi Sutton’s reply proving mere consolation for the hosts.
The ruthless Stags dominated the first half, with on-loan Leicester centre-back Reed scoring his first EFL goal in the eighth minute when he drove in from 15 yards after Aden Flint rose highest to meet Maris’ corner.
Akins then made the points safe before the break by netting twice in quick succession.
The 34-year-old striker fired home from just outside the penalty area in the 36th minute after home goalkeeper Mark Oxley had denied Davis Keillor-Dunn and Ollie Clarke had thumped a follow-up attempt against an upright.
Akins then stretched out a leg to divert Keillor-Dunn’s firm cross into the net from close range two minutes later.
Mansfield made it 4-0 in the 73rd minute when Maris beat an exposed Oxley from eight yards after being teed up by the menacing Keillor-Dunn.
The hosts’ late riposte saw Sutton’s deflected edge-of-the-box effort strike the underside of the crossbar and bounce over the line.