|Rossi, left, congratulates Lorenzo after the Spaniard's third-place finish was more than enough for the title [AFP]
Spain's Jorge Lorenzo clinched his first MotoGP world title as outgoing champion Valentino Rossi signed off in style by winning the Malaysian Grand Prix.
Yamaha rider Lorenzo finished third, having only needed a top-10 finish to lift the title with three races remaining after Sepang.
After starting on pole position the 23-year-old took few risks, easing off with two laps remaining and pulling a wheelie over the finish line.
Yamaha teammate Rossi put in a vintage performance on Sunday to win the race ahead of Italian compatriot Andrea Dovizioso on a Honda.
Lorenzo's triumph was assisted by injuries to his main rivals, Rossi and the absent Dani Pedrosa, but the Spaniard celebrated his win in style, flanked by team members dressed as video game characters while the rider held up a 'Game Over' sign.
"Today is the happiest day of my life and I am looking forward to celebrating it. It's a dream come true and it doesn't get any better than this," Lorenzo said.
1 V Rossi (ITA) Yamaha
2 A Dovizioso (ITA) Honda
3 J Lorenzo (ESP) Yamaha
4 B Spies (USA) Yamaha
5 A Bautista (ESP) Suzuki
6 N Hayden (USA) Ducati
7 H Aoyama (JPN) Honda
8 M Simoncelli (ITA) Honda
9 M Melandri (ITA) Honda
10 R de Puniet (FRA) Honda
11 H Barbera (ESP) Ducati
12 M Kallio (FIN) Ducati
Dovizioso also made an impressive start and was all over the back of Lorenzo on an eventful first lap that saw Rossi pushed back to 11th place and Australian Casey Stoner's hopes of a repeat Malaysia victory dashed with a crash on the final bend.
The leading pair pulled away from the chasing pack in the early laps as fan favourite Rossi delighted his massed local support base by weaving his way through the field to third place in hot pursuit of a sixth Malaysian victory in the premier class.
Rossi bridged the gap to the leading duo just as Dovizioso took the lead on the start of lap nine as Lorenzo appeared to be already settling for a top-three finish rather than challenging for a win.
The packed grandstand was soon on its feet when Rossi took the lead for the first time on lap 11, first passing Lorenzo and then Dovizioso as the 20-lap race became a two-way dogfight between the Italians.
Rossi and Dovizioso swapped positions twice on the 16th lap before the former managed to put enough daylight between himself and his compatriot to take the chequered flag for the first time since the opening race of the season in Qatar.
Spaniard Toni Elias won his inaugural Moto2 world championship after securing fourth place in Malaysia.
The race was won by Italian Roberto Rolfo ahead of Alex de Angelis of
In the 125cc race, Marc Marquez, who won the Japan Grand Prix last week, took the 18-lap race.
The result moved the Spaniard into the overall championship lead with 247 points, three ahead of compatriot Nicolas Terol.