The centre-back powerfully headed in a superb Kevin De Bruyne cross to give City the lead after 30 minutes.
Michail Antonio equalised for the visitors but fellow defender John Stones got the winner in the second half, meaning the duo have now scored more goals than they have conceded when starting together for City.
Dias was pleased to get his name on the scoresheet but also voiced his appreciation for the players around him.
“Yes, I’m very happy. I’m happier with the win but obviously very happy with my first goal with this shirt.
“To be surrounded by these top players makes it easier. The mentality everyone has makes the group, that makes the team.
“It felt good, sometimes it is the strikers, sometimes it is the wingers, sometimes it is the midfielders, but today it was us. Everyone can decide the game. Everyone is completely involved.
The Portugal international also spoke about the return of Sergio Aguero, the brilliance of De Bruyne and the key to keeping the good form going.
Watch the entire interview via the video above.
Interviews
Dias delighted after scoring first City goal
Ruben Dias has expressed his happiness at scoring his first goal for City, helping the team to a 2-1 Premier League victory over West Ham United.