Complex sentence: Di Grassi struggled at the Chinese Grand Prix which saw him start from the pit lane but trundled behind Lotus driver Karun Chandhok until he pulled into the pit lane to retire with clutch failure after nine laps.
Split into simpler sentences: Di Grassi struggled at the Chinese Grand Prix which saw him start from the pit lane. He trundled behind Lotus driver Karun Chandhok until he retired with clutch failure after completing nine laps.