The melee over the final laps resulted in some unexpected results just behind, with Anthony West
showing his prowess in tricky conditions yet again to claim an excellent fourth for MZ, while Kenny Noyes would break his 2011 points' duck in remarkable style by taking fifth.
Colombian Hernandez, who is tipped to be moving to MotoGP aboard a BQR CRT machine in 2011, was a frustrated sixth, ahead of Tech 3 duo Mike di Meglio and Simeon, the latter Belgian losing ground in the closing stages.
Max Neukirchner made it a fine day for MZ in ninth, ahead of Julian Simon, while Andrea Iannone sealed third in the standings by finishing 11th, compared to Alex de Angelis
Elsewhere, newly crowned champion Stefan Bradl suffered only his second DNF of the season after crashing out on lap five, while Britons Smith and Scott Redding finished well outside the points after taking separate tumbles in the early stages.
1. Pirro (Moriwaki) 46m 22.205s
2. Kallio (Suter) +6.150s
3. Aergerter (Suter) +6.363s
4. West (MZ-RE) +8.843
5. Noyes (FTR) +9.229s
6. Y. Hernandez (FTR) +9.926s
7. Di Meglio (Tech 3) +10.115
8. Simeon (Tech 3) +10.385s
9. Neukirchner (MZ) +13.018s
10. Simon (Suter) +13.365ss
23. Smith (Tech 3) +1m 15.394s
30. Redding (Suter) +1 lap