Alvaro Bautista won the 250 GP in Malaysia, but it was Simoncelli who claimed the big victory as a podium finish was enough to grant him the championship.
Marco Simoncelli places third in the 250 clash at Sepang, but this gave him enough points for an unsurmountable lead over the competition in this year's 250cc championship.
Bautista knew that winning in Malaysia wouldn't be enough, so he tried some strategy, slowing the pace to try to put some traffic in front of his rival. But in the end the Spanish rider saw it wasn't working and instead pulled away, gunning for the win for maximum points.
Aoyama, who started from pole position and won the race here last year, managed to overcome news about the future of the KTM 250 team to finish in second place.
Japanese rider Takahashi claimed 4th for JiR Team Scot 250 and Spaniard Alex Espargaro took fifth on his Lotus Aprilia.
1 Alvaro BAUTISTA SPA Mapfre Aspar Team Aprilia 42'56.428
2 Hiroshi AOYAMA JPN Red Bull KTM 250 KTM 42'59.014
3 Marco SIMONCELLI ITA Metis Gilera Gilera 43'04.771
4 Yuki TAKAHASHI JPN JiR Team Scot 250 Honda 43'07.460
5 Aleix ESPARGARO SPA Lotus Aprilia Aprilia 43'10.274
6 Alex DEBON SPA Lotus Aprilia Aprilia 43'10.702
7 Roberto LOCATELLI ITA Metis Gilera Gilera 43'11.529
8 Ratthapark WILAIROT THA Thai Honda PTT SAG Honda 43'13.415
9 Thomas LUTHI SWI Emmi - Caffe Latte Aprilia 43'21.784
10 Lukas PESEK CZE Auto Kelly - CP Aprilia 43'23.274
11 Fabrizio LAI ITA Campetella Racing Gilera 43'46.335
12 Karel ABRAHAM CZE Cardion AB Motoracing Aprilia 43'46.516
13 Alex BALDOLINI ITA Matteoni Racing Aprilia 44'02.244
14 Simone GROTZKYJ ITA Campetella Racing Gilera 44'11.972
15 Imre TOTH HUN Team Toth Aprilia Aprilia 44'16.333
16 Manuel HERNANDEZ SPA Blusens Aprilia Aprilia 44'32.318
17 Daniel ARCAS SPA Blusens Aprilia Aprilia 44'57.145
18 Doni Tata PRADITA INA Yamaha Pertamina Indonesia Yamaha 45'25.270