Gareth Roderick justified his promotion in Gloucestershire's batting order by scoring 71 to help the home side open up a first innings lead of 144 on day two against Worcestershire at Cheltenham.
Starting the second day on 83 without loss in reply to 182, Gloucestershire were bowled out for 326, with Chris Dent (79) and Alex Gidman (62) also posting half-centuries.
By the close Worcestershire had progressed to 31 without loss in their second innings and trailed by 113.
Roderick, who earned a Gloucestershire contract by scoring more than 1,000 runs in a season for Cheltenham Cricket Club in the West of England Premier League, relished being back in the town.
The 21-year-old South African wicketkeeper-batsman was given a chance at number three, rather than his customary middle-order position, when skipper Michael Klinger fell for 36, caught at point off a delivery that seemed to stop on him, with the total on 101.
Dent, unbeaten on 56 overnight, looked aggrieved to be judged stumped trying to sweep Moeen Ali, having hit 13 fours in his 114-ball innings. At 129-2, Gloucestershire were still 53 runs adrift.
But Roderick was set by then and found a reliable partner in Gidman as the home side moved into the lead before lunch, which was taken on 193-2.
Gidman was first to his half-century in the afternoon session, off 76 balls, with seven fours, but his young partner lost nothing by comparison.
Roderick hit seven boundaries of his own in progressing to fifty off 107 deliveries and it was Gidman who went after a stand of 105, caught behind by Ben Cox, diving to his right, off Alan Richardson.
That was 234-3 and 28 more runs were added before Roderick was taken at slip by Daryl Mitchell, edging a ball from off-spinner Ali.
Before a run was added Benny Howell was run out by Alexei Kervezee's throw, attempting a single as Hamish Marshall played a delivery to backward point.
Marshall contributed 20, but when he was bowled to give seamer Graeme Cessford his first Championship wicket Gloucestershire went on to lose their last four wickets for 25, Gareth Andrew (3-56) claiming all but one of them.
Worcestershire openers Mitchell and Matthew Pardoe survived 18 overs to the close with few alarms.