Foret inherited third and then second at the expense of Rea, before going in hunt of Davies, who was continuing to control the pace out front.
The Frenchman could do nothing about Davies, however, who – having claimed a personal best finish of second at Donington Park – went one better to record a popular maiden victory by a clear seven seconds.
Foret held onto second for a strong first finish of the season, while Parkes launched an outstanding recovery to snatch third position in the closing laps.
The Kawasaki man's performance is particularly significant as it places him just three points behind Scassa in the overall standings, despite having not yet won a race. Davies, meanwhile, is now just five points adrift.
Third position had looked to be going the way of Rea, but the Step Racing rider would crash with four laps remaining, dropping him down to 17th position.
Robbin Harms maintained his consistent start to the year on his privateer Honda with a determined ride to fourth, ahead of David Salom, Roccoli, James Ellison - who was rewarded with seventh after a tough weekend – Roberto Tamburini, Miguel Praia and Rea's team-mate Vladimir Ivanov.
Outside the top ten, Team Hungary Toth scored its best results with Balazs Nemeth in 11th and Imre Toth in 12th, ahead of Pawel Szkopek, Bastien Chesaux and Danilo Dell'Omo.