Just three behind second-placed Alvechurch after the win, the Blues got off to a great start at Westfield Lane when Jacob Hazel grabbed his 36th goal of the season after just six minutes.
The home side had to wait until the hour-mark for the second goal to arrive when a well-worked free-kick was finished off by Sam Liversidge.
Castle offered little in response and remain four points above bottom-markers Sheffield FC, who possess two games in hand.
Image courtesy of Onion Bag Photography
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