On 25 March 2010, Cywka joined Championship side Derby County on loan till the end of the season. He made his debut for Derby as a late sub in a loss against Ipswich before starting the final four matches of the season. In April, Derby manager Nigel Clough began talks to extend his stay at Pride Park Stadium into next season. On 25 May, it was announced that he would sign a two-year contract with Derby on a free transfer on 1 July, after turning down Wigan's extension offer due to his desire for first team football.