Guardiola's prized poacher Erling Haaland struck the second-half winner in a victory that slashed the gap at the top of the table to three points, with City having a game in hand.
Guardiola, who was wildly animated all night, scoffed when asked if he enjoyed the game.
"Enjoying I don't think is the right word," the Spaniard said. "It's fine. Hope, that game gave us hope. That's all.
"I said to the guys after the game, enjoy the moment, but don't lose the focus right now. We are there, but the reality is who is the top of the league? We are not," Guardiola added.
"Goal difference (if the two teams finish even on points), who is better? They are. But of course, we've got hope, to still extend the chance to fight and to live."
Guardiola has made a habit of breaking Arsenal's hearts, his Manchester City sides stalking them through spring before unleashing relentless late‑season surges that turn belief into dread and title races into familiar blue victories.
He described Sunday's bruising contest as worthy of the title race, praising Arsenal's resilience and physical edge.
"People say they don't have momentum," he said. "When you see them play and compete in duels, long balls, second balls and set pieces, they are an extraordinary team. Otherwise you cannot be top of the league all season."
The City manager called the clash "the best advert worldwide and for England."
In the heart of the storm was Haaland, back scoring in the league for the first time in two months and locked in a ferocious duel with Arsenal defenders William Saliba and Gabriel.
A tussle with Gabriel left Haaland's shirt badly torn and he tossed it into the crowd.
"I would not like to be Erling Haaland and battle with William Saliba and Gabriel," Guardiola said with a smile. "To be honest, I prefer to read a book."
Haaland embraced the chaos.
"I think it's always like this, a lot of fighting," the 25-year-old Norwegian said. "It's up to others to decide if I won that battle or not. I scored the goal, so I won the battle in that moment. It was decisive, and we win."
Guardiola said the striker's mid-season scoring drought reflected the toll of a relentless campaign.
"A guy so big, playing every three days during November, December, January, February, to sustain that with his body, it's not easy," he said.
Guardiola ended the night by saluting captain Bernardo Silva, who will leave at season's end after nine years at City.
"If I talk a lot one day I cry," Guardiola said. "So I just say thank you from the deep of my heart. When we write 'the legend,' it has to be in capital letters. He's a special, special player."
City will draw level on points with Arsenal, and dislodge them from the top of the table, with a victory at 19th-placed Burnley on Wednesday.