A Harry Kane goal with just 15 minutes on the clock was enough for Spurs to defeat the champions and put a big dent in their Premier League title bid.
Eyebrows were raised in some quarters at Emerson being given a start, especially with big money January signing Pedro Porro on the bench.
The full-back completed the full 90 minutes though and Stellini believes he turned in a perfect performance.
He admits that Emerson has things to work on in his game, but lauded him for his display against Pep Guardiola’s men.
Stellini told the BBC’s Match of the Day programme: “We have seen him play great games. Against City last season it was similar.
“Today he was a good player and he used to be better when you are winning.
“He has to improve in other situations but today he was perfect.”
The Tottenham assistant revealed the squad have had a tough week with Antonio Conte being over in Italy for surgery, but feels the group rose to the occasion.
“Absolutely a great performance for all the team and all the staff.
“We knew it was a tough week without Antonio. Everyone forced themselves to another level. We are happy for them, for the club, for Harry and for Antonio as well.
“Antonio is far from us and he is not very well at the moment. He had to stay away from the game and stay calm but I’ve just spoken to him and he is very happy”, Stellini added.
The win sees Tottenham, in fifth, move to within a point of fourth placed Newcastle United, though they have played a game more than the Magpies.
