Complex sentence: Rosberg's season began with a front row start and then victory in the 2016 Australian Grand Prix giving him the lead of the World Championship for the first time since 2014 and followed this up with another front row start and victory in the 2016 Bahrain Grand Prix.
Split into simpler sentences: Rosberg's season began with a front row start and then victory in the 2016 Australian Grand Prix giving him the lead of the World Championship for the first time since 2014. He followed this up with another front row start and victory in the 2016 Bahrain Grand Prix.