John Stones believes Manchester City came through a 'tough test' after grinding out a 2-1 victory over Napoli to maintain their 100 per cent start in this season's Champions League.
City stormed out of the traps with goals from Raheem Sterling and Gabriel Jesus inside the opening 13 minutes but Napoli wasted a gilt-edged chance to half the deficit when Dries Mertens' penalty was saved by Ederson just before half-time.
The Brazilian goalkeeper was a towering presence in the City goal and the only time his net was breached was through Amadou Diawara's 73rd-minute spot-kick.