In 2010, Dernbach was selected for the England Performance Programme tour of Australia and subsequent England Lions tour of the West Indies where they participated in the domestic Regional Four Day Competition. He took 19 wickets at an average of 15.63, making him the leading English bowler.
He was called up to the senior team as a replacement for Ajmal Shahzad for the knock out stages of the 2011 Cricket World Cup but was not picked to play. At the beginning of the English season, he was then picked for the Lions to face the touring Sri Lankans. He took 9 wickets in the match. His performance saw him included in the senior squad for the second Test after an injury to James Anderson. He had to wait until the limited overs games to make his debut; taking 1-18 in his first Twenty20 International and 2-25 in his first ODI.
Derek Pringle has described him as a fast bowler who is capable of obtaining conventional and reverse swing, as well as of deceiving the batsman by bowling a variety of slower balls.