Career-best scores from Billy Godleman (211 not out) and Tom Lace (143) helped Derbyshire to a lead of 110 on Day Three of the Specsavers County Championship game against Glamorgan.
The pair put-on a record partnership of 291, the highest for any wicket for Derbyshire against Glamorgan, while Harvey Hosein brought up his half-century with the penultimate ball of the day.
Derbyshire will resume on 504-4 in Swansea, with Godleman and Hosein (53 not out) at the crease.
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