Most of Saturday's action centred around Julian Speroni. Lucky not to be sent off in the first half for handling outside the box, Speroni went on to make a number of key saves.
Ambrose finished neatly from Derry's header and despite facing a Derby barrage Palace held on.
The team will need all the confidence they can get for Saturday's trip to W.B.A. Albion managed a 5 - 0 win away at Middlesbrough on the weekend.