Paul Charnley's side fell behind in the ninth minute but hit back in the second half thanks to Jerome Murdock who netted in the 59th minute.
Sphinx continued to press and four minutes from time, striker Luke Hopkins got the winner to keep Sphinx in second place in the Midland Alliance table.
Sphinx travel to Oadby on Tuesday night and a report will appear on this site.
Coventry Sphinx Reserves did not fare so well losing 6-1 at home to Bromsgrove Rovers in a Midland Combination Reserve Division fixture.