This is the club's sixth successive Champions League campaign but they are still to really come of age in the competition despite reaching the semi-finals in 2016 and then bringing in two-time winning manager Guardiola.
"I don't know now if we're able to compete for the titles because we're in the process of growing".
Asked if the incident could make the goalkeeper hesitant in future, Guardiola said: "I could understand that feeling if he felt that, but in today's training session there were two or three long balls and he was there".
"Now is just the warming up and in February when us English teams, we are trying to survive after the winter period, they will be fresh and ready after these warm-ups".
It's a dream to be here again for a club like Manchester City.
If City do not win in Holland this week it could mean they need to go to the Ukraine to face Shakhtar Donetsk last (in December) needing a result. The gap was so close between Arsenal, Liverpool, Manchester United and us. We start our road. I know from my experience even in Barcelona and Bayern Munich how it is to qualify for the next stage. "We have often beaten big teams here in recent years". Hopefully, the players can enjoy being here.
The Rotterdammers have started the defence of their title with four victories from four, notching 12 goals to catapult van Bronckhorst's troops back to the top of the table at this early stage.
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Canelo would go on to lose that fight by majority decision, which is to this day his only competitive loss. Right now for us, it's huge. "I always prepare myself to give the best".
Wednesday's trip to Feyenoord is City's first Champions League match of the season.
Stones, speaking alongside Guardiola at the pre-match press conference on Tuesday, said: "Ederson has got on with it straight away".
"It's just a sporting decision". Six players finished contracts and the only one who stayed was Yaya, because he's a special player.
"But the decision why he hasn't played this season and is not in the squad - he knows the reason why".
Another player who will not feature is captain Vincent Kompany, who continues to be troubled by the calf injury.
City's players will certainly not be taking the game lightly, with more than enough of them having tasted disappointment at the group stage before.