Saints crashed to another heavy defeat at Pack Meadow, as Chelmsley Town, who had notched up three goals in a one-sided first half, turned the screw after the break to hit five more, writes Paul Vanes.
Town opened with a flourish with Saints keeper Simon Reading diving to save at his left-hand post, with Karl Douglas then shooting into his grateful arms.
In the 18th minute, Saints were saved by the woodwork when Stephen Sadler’s shot hit the top of the bar and, hemmed in, were struggling to cross the half-way line.
In a rare attack, Southam did win a corner, which came to nothing.
Lee Rycroft, who had been struggling with a hamstring problem, was replaced by Josh Marshall in the 27th minute, and the substitute was soon into the action, clearing a Gary Turner corner off his own line.
All the Town pressure had to pay off and they took the lead in the 31st minute when Jem Mills coolly lobbed Reading, doubling their advantage a couple of minutes later when a Douglas cross was headed in by James Sawyer.
Southam had their first shot at goal in the 41st when Suki Nijjar fed a through ball to Josh Turton, but home keeper James Kelly was in the right position to collect.
Chelmsley ended the half as they began it, on the attack, when left-back Stephen Sadler popped up on the right side edge of the penalty area to shoot narrowly wide.
The third goal came when Danny Charlton rode two tackles inside the box and thumped in a shot which gave Reading no chance.
The second half began disastrously for the visitors as Reading left his line to collect a harmless long ball, only for Ben Nicholson, on the 18-yard line and facing his own goal, to stretch out and perfectly lob the ball into the gaping net.
Chelmsley’s fifth goal was again an own goal as Adam Brannagan, trying to keep out a knee-high ball, only succeeded in putting it past Reading from close range.
Both sides made substitutions, Liam Kelly, Lee Yonwin and Jason Gordon for Town and Dylan Timms and James Keller for United.
Town continued to swarm over the half-way line and, from a left-wing cross, Sawyer was given the space to chest home their sixth goal.
Following a meaty challenge that saw retaliation, a fracas developed and referee Peter Price was left with no alternative but to send off Turner of Chelmsley and Mark Ling of United, with one or two other players lucky not to join them.
As the game entered injury time, Chelmsley added their seventh goal through Jem Mills and, in the third minute of added time, he completed his hat-trick.