Having beaten the same opponents at the weekend to lift the Carabao Cup, City moved a step closer to clinching the Premier League title with a clinical performance at the Emirates Stadium on Thursday.
Bernardo Silva, David Silva and Leroy Sane scored in the first half as the runaway leaders restored their 16-point cushion over nearest rivals Manchester United in the table.
Guardiola's squad now need to win just five of their remaining 10 games to be crowned champions after what their manager described as an "amazing result" on the road.
"Mentally we were strong. We were clinical. We scored three outstanding goals," the Spaniard told BBC Sport.
"After that it was not easy — the first 15 minutes of the second half we were poor. Still, it's an amazing result for us.
"We are out of the FA Cup and we have won the League Cup. Now it's just two competitions, and you fight for one of them for 10 months.
"These are the last steps to be champions; you keep going until the end. We have to win five games. We don't think too much — now we play Chelsea.
"Hopefully we have the desire to win, to be the best team in England. We forget that we are tired."