Hart believes it was the perfect riposte to critics who claim that City are divided and lack the togetherness to retain their Premier League title.
"The spirit has never been in question," said Hart. "We have that and we have quality. Those two combined makes us the team we are.
"It's not a quality we've developed. It's just instilled in the people. It's a group of winners. Twenty players who play to win – we're lucky with that. We don't turn up to tick boxes or make people happy, we turn up to win.
"We showed why we are champions and hopefully we will be again."