Complex sentence: Vettel found himself leading behind the safety car, and upon the resumption of racing, a battle between Vettel, Alonso and Button began, Vettel being able to hold the two former world champions behind him, despite being on tyres that had lasted since lap 16.
Split into simpler sentences: Vettel found himself leading behind the safety car and when racing resumed a battle between Vettel, Alonso and Button began. Vettel held the two former world champions behind him, despite being on tyres that had lasted since lap 16.