Lockie Ferguson took two wickets on his red ball debut for Derbyshire, but Sussex’s Ben Brown hit a fine 116 as the hosts closed Day One on 400-7 at The 1st Central County Ground.
Hardus Viljoen and Tony Palladino also claimed two wickets as Derbyshire had Sussex 115-4 at the end of the first session.
But defiant batting from Brown, who was well supported by Harry Finch (82) and David Wiese (89 not out), left the South Coast side in a strong position after the opening day.
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