Winger Sterling won the penalty that Sergio Aguero dispatched early on and tormented the Black Cats defence all evening.
“He played amazing, but he also played well against Borussia Dortmund, Arsenal, St Johnstone,” said Guardiola, before adding: “We need people who stay wide, go to the byline or go inside. That is so important. He’s a fighter. Of course we want more of him, but I’m very happy, he’s a very nice guy. We want to help him to see the real Sterling.”
After sprinting out of the blocks, City conceded an equaliser from Jermain Defoe and found stubborn opposition in David Moyes’ side.
The breakthrough came with just three minutes of normal time remaining when Jesus Navas’ cross was turned into his own net by Patrick McNair.
Overall, Guardiola declared himself happy with his Premier League debut.
“For the first game at home it was going to be a question about the Premier League - you saw the results of the other games.
“I’m very pleased about the performance we achieved. In the first 10-15 minutes we played good. The second half until the goal from Defoe we played really, really well, we made good build ups, with John, Kolarov, Fernandinho, Gael and Sagna.
“Maybe we should attack quicker but that is normal in the moment we are. We have to learn. I saw many good things about the spirit of the team. We have to build something from that.”
Guardiola was quizzed about his team selection - the boss opted for Willy Caballero in goal while Yaya Toure, Eliaquim Mangala and Samir Nasri weren’t in the matchday squad - but said he was satisfied with the way his players are shaping up.
He reflected: “Yaya trained really, really good, Samir is training amazing, so I’m really impressed by his quality. Mangala, you know how professional he is. At the end I have a squad and I have to decide what I see. I have to create the team spirit. Today I chose this line up but that doesn’t mean they won’t play in the future.”
He added: “Today I decided the team because of many many reasons. I wanted aggression without the ball, to create a good build up. I think with Willy, with John and Kolarov and Fernandinho they did a really good job.”
When asked if he is a manager that sticks with a number one Guardiola added: “Hart can play - other players in the squad can play. I was focused on Sunderland. From tomorrow morning I will decide what’s best for the team (ahead of Steaua).”
Guardiola also confirmed he chose David Silva as skipper because he was the longest serving member of the starting XI.
