The midfielder slotted the Robins' 42nd minute opener during a 3-1 victory that relegated their opponents from Sky Bet League One.
Elsewhere Hayden Mullins played the duration of Notts County's 1-0 win at home to Crawley Town as the Magpies continued their battle to stay in English football's second tier.
The duo of Birmingham City loanees had actually faced each other at Ashton Gate on Good Friday.
And it was Elliott who found himself on the winning side as Bristol City beat Mullins' side 2-1.
Meanwhile young Blues trio Nick Townsend, Charlee Adams and Koby Arthur were all in action for Lincoln City in the Skrill Premier over the course of the Easter Bank Holiday.
Goalkeeper Townsend played the duration of the Imps' successive 1-0 victories over Cambridge United and Wrexham on Friday and Monday respectively. Winger Arthur played the final seven minutes of the win at home to Cambridge and was a 78th minute substitute at Wrexham. Midfielder Adams played 85 minutes against the Us but did not figure in North Wales.
In the Skrill North, full-back Ryan Higgins featured for Leamington as the Brakes held Boston United to a goalless draw at home on Saturday before battling back to level 3-3 during an entertaining game at Gloucester City on Easter Monday. Elsewhere, despite back-to-back 2-1 defeats to Hednesford Town and Brackley Town on Saturday and Monday respectively, winger Viv Solomon-Otabor's Oxford City are all but secured of their place in non-league football's second tier for a further season. Oxford sit +13 goals ahead and level on points with Stalybridge Celtic who sit third from bottom.