Manager Richard Kay made just one change from the side that started at Pershore, with Callum Stewart replacing Ben Tennant at full back. Strong winds and rain saw this become a test of stamina as well as football by the end but, having raced to a 4-0 lead at half-time, Southam were always in control.
Leading scorer Josh Dixon gave Southam an early lead and defender Adam Neale headed home to double the advantage in the 20th minute. It was another defender in Craig Watkin who made it 3-0 with a powerful header from an Ethan Champkins corner before player of the match Stewart surged forward to set up Champkins for the fourth and put Southam firmly in the driving seat at the break.
Cirencester pulled one back from a corner at the start of the second half, but Shane Osborne made it 5-1 to quash any hopes of a home revival. A left-foot volley from captain Simon Barby extended the lead further and, although the home side got a second, the outcome was never in doubt.
Southam United: Hudson, Harris (Dunn), Stewart, Neale, Watkin, Yeates, Ethan Champkins (Newell-Hollely), Ellis Champkins, Osborne, Barby [Capt.] (Goddard), Dixon (Drummond)