Luke Hopkins scored twice in the opening ten minutes and it was 3-0 when Michael Husserbury netted in the 26th minute.
The visitors pulled one back on the half hour mark through Sam Beasley, only for Robbie Stevenson to hit a fourth in the 32nd minute.
Causeway scored a second ten minutes from time through Arron Lloyd but Sphinx who travel to Westfields in Tuesday night for a league game picked up some much needed league points.