The Warriors put themselves under pressure in the opening stanza after conceding three set re-starts and while they defended well it was only a matter of time before they cracked.
Waqa Blake scored his first try in the 12th minute after Reed Mahoney threw a long pass behind Reagan Campbell-Gillard from dummy half for the Eels centre to stroll over the Warriors line.
The Warriors refused to give up and after a sustained period of pressure on the Parramatta line, Wayde Egan and Adam Pompey combined to put winger Marcelo Montoya over eight minutes before halftime.
Trailing just 10-6 at halftime, the Warriors must have thought they were a chance of causing an upset but errors and ill-discipline again put them under pressure and the Eels made them pay.
Wests Tigers-bound Kiwis second-rower Isaiah Papali'i scored in the 55th minute after a reverse pass from Mahoney and captain Clint Gutherson virtually sealed the win three minutes later after Montoya was unable to take a Mitchell Moses bomb.
Winger Maika Sivo then completed a dominant second half Parramatta performance when he raced down the left touchline to score.
Photo: PHOTOSPORT Caption: Marcelo Montoya