The Sphinx support travelled in numbers to Marston Road and saw Kelvin Phillips put Sphinx ahead in the 18th minute.
Danny McSheffrey's side kept up the pressure against the Conference North side and they were awarded a 35th minute penalty which Kyle Rhodes converted.
It stayed at 2-0 until the 77th minute when Kasiama pulled one back for Chrissie Brindley's side.
Four minutes later, Jerome Murdock had the support and Sphinx bench going berserk when he hit a third for Sphinx.
Thorley converted a penalty with six minutes remaining but it was Coventry Sphinx who picked up the winners cheque for £4,500 and booked their place in the Third Qualifying Round against Bedworth at Sphinx Drive on Saturday October 10th.