Garstang go into Saturday’s Division One North Cup tie with Holker OB, buoyed by last weekend’s 2-0 win over Nelson.
They started well at the Riverside with half-chances coming and going before Nelson were awarded a penalty.
However, Garstang keeper Will Kitchen dived and kept out the penalty at full stretch for his second spot-kick save of the season.
Two minutes before the break and Garstang led when Jake Salisbury collected a clever pass and slotted home.
A minute into the second half and it was 2-0 as Josh Westwood headed on Kitchen’s free-kick and, with the defence slow to react, Alan Coar got behind them to score.
In front of another sizeable Riverside crowd, Garstang were able to comfortably see out the remaining time to secure a deserved three points.