Jim Allenby hit an unbeaten half-century to help Glamorgan move into the lead against Division Two rivals Worcestershire at the SWALEC Stadium.
The experienced all-rounder finished the second day of the LV= County Championship fixture on 71 not as Glamorgan closed on 235-7, meaning they are 112 ahead of their opponents at the halfway stage.
Opener Ben Wright (40) and Marcus North (48) also made crucial contributions in what has so far been a low-scoring contest.
Worcestershire seamers Alan Richardson and Gareth Andrew claimed three wickets apiece to keep their side in the hunt, though they were always struggling after being dismissed for 123 on day one.
After an hour's play was lost to rain in the middle of the morning session, Andrew made the early breakthrough by bowling Will Bragg to leave Glamorgan 22-1.
The same bowler also dismissed Stewart Walters but North and Wright gave the Glamorgan innings some impetus by putting on a valuable 59 for the third wicket.
Ex-Sussex batsman Murray Goodwin mustered only a single before being removed by Richardson, meaning the veteran right-hander is still has to make double figures for his new employers.
North fell just short of his his half-century when he was trapped before to Richardson, while skipper Mark Wallace contributed just a single to his side's score.
However Allenby - who became the first Glamorgan player to reach 50 this season - and Graham Wagg put on a seventh-wicket stand worth 63 before the latter fell to the second new ball for 24.