Rhys Murphy gave the visitors the lead but Saidou Khan hit an instant equaliser two minutes later.
Debutant Luke Croll then turned the scoreline around, finishing from inside the area.
Kabongo Tshimanga came off the bench to add a third before Southend’s Sam Dalby missed an injury-time penalty.
Both sides ended a man down as Calvin Miller and Zak Brunt were sent off.
Here are Liam Norcliffe’s player ratings...
Kabongo Tshimanga came off the bench to add a third before Southend’s Sam Dalby missed an injury-time penalty.
2 / 4