Pol Espargaro crashed out early with 16 laps remaining. The Tuenti HP 40 rider had work to do after qualifying down in seventh and was carried away limping from his tumble with one of his boots missing.
Italtrans rider Takaaki Nakagami appeared to suffered rear tyre problems and had a gearbox issue which caused him to pit and retire when running near the front.
British rider Danny Kent was 18th for Tech3 and also improving was his fellow countryman Kyle Smith in 21st aboard his Blusens Avintia.
Moto2 returns in Jerez over the weekend of the 3-5 May.