Brazilian striker Gabriel Jesus came off the bench to score the winning goal for Manchester City against Leicester City.
Aguero had earlier missed from the spot before he was replaced by Gabriel Jesus with 13 minutes to go.
Jesus scored the winning goal just three minutes after coming on to hand Manchester City the maximum points and move them seven points clear of Leicester City in the second place race.
Guardiola hailed his players for another battling performance in the face of their ban
“Don’t ask me about the attitude of these guys,” said Guardiola. “You still doubt what they have done.
These players have won seven titles in the last eight [domestic] competitions.
“Today, after missing the penalty, see the reaction we had against an incredibly good team, not just for where they are in the table right now but the way they played, in general, this season. It was an incredible test for us.”
Manchester City has now missed five of their seven penalty kicks in the premier league this season.
The Citizens have kept successive clean sheets in the Premier League for only the second time this season (also in October 2019).
They have also won six of their last seven league meetings with Leicester City (L1), as many as their previous 21 such clashes.