Billy Godleman (86*) and Tom Lace (78*) struck half-centuries on Day Two of the Specsavers County Championship game against Glamorgan.
Graham Wagg (100) hit a 102-ball century earlier in the day to help Glamorgan to a first innings score of 394, before Godleman and and Luis Reece put on 52 runs for the first Derbyshire wicket.
The visitors will resume on 221-2, with Godleman and Lace at the crease in Swansea.
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