By Chineze Ogugua
Marc Marquez defended the Aragon title he won last year and opened a 16-point lead at the top of the world championship standings with 224 points.
Dani Pedrosa finished second and Jorge Lorenzo, who led the race, was third while nine-time champion Valentino Rossi, who suffered a double leg fracture only three weeks ago, finished fifth.
The Italian was second behind three-time champion Lorenzo for part of the race before Marquez, Pedrosa and Maverick Vinales moved ahead of him.
Rossi, who is fifth on the standings, will have to put in a stiffer fight to keep up with the race for the No.1 spot as he prepares for the next race, which is the Japan Grand Prix, in Motegi on 15 October.