Fonsi Nieto kept current Championship leader Manual Poggiali at bay through a thrilling final few laps as the Spanish rider finally scored his first win of the year aboard the Team Repsol Telefonica Movistar Aprilia.
Nieto crossed the finishing line of the 2.5-mile Donington Park circuit just three tenths of a second ahead of the current 250cc Championship leader after 27 fast-paced laps around the sun-drenched venue.
Assen winner Anthony West completed the podium after a last corner scramble with eventual fourth place finisher Toni Elias and fifth place Robby Rolfo, all three riders finishing less than three seconds behind the two leaders.
Sebastien Porto finished a rather distant sixth on his Telefonica Movistar Junior Honda but was almost half a minute behind the front quintet with veteran Franco Battaini seventh, Randy de Puniet eighth and front row qualifier Naoki Matsudo ninth.
British wildcard Jay Vincent, driving for his fathers Padgetts Racing team performed well to take eleventh place, less than five seconds behind tenth placed Alex Debon. Fellow Brit Chaz Davies also rode out of his skin in front of a massive home crowd to finish 13th, exactly two tenths of a second behind Hector Faubel but more than ten seconds clear of Jakub Smrz and Dirk Heidolf, who completed the points scorers.
Katja Poensgen came home 19th and last on her Dark Dog Molenaar Honda but both other British wildcard riders; Lee Dickinson and Phillip Desborough failed to finish.