Unai Emery revealed the mid-term team speech that inspired Arsenal's famous return to Tottenham in the North London derby.
The Gunners were dug into a hole behind the Spurs 2 to 1 at the break at Emirates.
But Pierre-Emerick Aubameyang, Alexandre Lacazette and Lucas Torreira scored in the second half to win a famous 4-2 win.
"First, it was to stay calm," Emery said. "We changed little details, but what was most important to me at halftime, is to be calm, to give them confidence because maybe yesterday We were 1-0 and we finished the half 2-1, the best moments of the first half, to repeat in the second half.
"Change something special – I changed two players at halftime, but not because Iwobi and Mkhitaryan were struggling, but because we had to change and push with different players.
"I explained yesterday that Aaron had experience in derbies like yesterday, and the second was that I thought we could do better with players having the ability to score against them."
The Gunners will travel to Old Trafford Wednesday to face Man United, who is eight points behind him to rank in the top four.