From here, Biaggi simply galloped away from the competition as he stretched his lead to a high of six seconds before easing back towards the end to finish four seconds up.
The battle for second was more closely fought, with Haslam next to pounce on Fabrizio, the Suzuki rider going considerably better than he did in race one as he dispatched with the Ducati on lap 14.
While Haslam went on to second, Fabrizio was forced to fend off Crutchlow, the Ducati rider conceding the position to his rival on lap twenty before snatching it back with less than two laps remaining.
Crutchlow settled for fourth to avenge his race one calamity, while Checa clawed back one position in fifth after Corser, whilst under pressure from the Spaniard, ran off the circuit on the final lap trying to defend. The BMW rider would end his day in a dissatisfied tenth.
Following on from his fifth place in race one, Sylvain Guintoli completed a lucrative points' haul in sixth, ahead of Shane Byrne, who benefitted from Corser's off and a second fall in three races for James Toseland, the former champion coming down at turn one on lap eleven.
Luca Scassa earned the kudos of winning out in a fight with Noriyuki Haga in eighth position, while Leon Camier finished just outside the top ten in 11th.
Elsewhere, Ten Kate Honda's dismal day ended with Jonathan Rea in 12th and Max Neukirchner 14th, while Chris Vermeulen notched up another single point with 15th on the Kawasaki.