Arsenal 'overwhelmed' by epic fightback: Arteta
Arteta's side fell two goals behind against lowly Bournemouth before battling back to secure a thrilling victory which keeps them five points clear of second placed Manchester City.
It is the first time in over a decade that the Gunners have recovered from a two-goal deficit to win a league game.
Thomas Partey and Ben White struck to made it 2-2 before substitute Reiss Nelson netted deep into stoppage-time.
"Everybody is overwhelmed. It was madness from the first seconds with that routine and we defended so poorly," Arteta said.
"Then we had to climb a mountain against 10 men behind the ball. We tried in every single way, we didn't score and suddenly we are 2-0 down from a set play."
Bournemouth led through Philip Billing, who scored the second-fastest goal in Premier League history as he turned home with just 9.11 seconds on the clock.
Marcos Senesi doubled the advantage after the break at the Emirates Stadium, but Arsenal showed the attitude of champions to secure a win that could prove a defining moment in the title race.
Nelson, 23, is out of contract this summer and was introduced off the bench for his first appearance since November 12, having also been sidelined with a thigh injury.
"It's been a rough couple of months for me, just coming back from injury and when that goal went in it was a great moment for me," Nelson told Sky Sports News.
"I have been here all my life. It means a lot to me. It was a great strike. I'm delighted with the goal and hope it is the first of many."
Nelson set up White's equaliser before scoring a superb 20-yard winner with the last meaningful kick of the contest as Arteta revealed he now has a selection headache.
"I always saw the potential (of Nelson). The talent and the desire for him to do it, but he's at a different level right now. I think emotionally, the experiences that he had helped him," Arteta said.
"Football-wise, it was my decision in the last two games not to play him because we had other options.
"But he was knocking on the door. He's been training really good and it's a good lesson for me and for the coaches that we need him and that he can be really important for the team."