"We'd done it in the week and then we did it Sunday but I wasn't in the team and I wasn't sure if I was playing or not and it wasn't until today that I found out I was in the back three, so that was good".
Goals from Alexis Sánchez and Mesut Özil, either side of Álvaro Negredo's equaliser lifted Wenger's team to sixth, seven points behind fourth-placed Manchester City, albeit with a game in hand. The three points were massive. "Despite sometimes hard situations, or some situations that lack clarity, we are professional people, our job is to perform and we can still perform", he said.
He confessed: "What we've done previously has not been good enough".
Earlier, Wenger said, "For us the clarity is there - we have to win every game to have a chance to get into the top four". "We were tested and maybe rode our luck on one or two occasions with crosses but we were committed and the back three worked well in the first half, we were solid".
Of his formation change, Wenger added: "It is the first time in 20 years - it shows even at my age you can change". "Of course, the opponents had a bit more of the ball than we're used to.
But sometimes when a team lacks confidence, just to change the system can help to believe in something different". We were vulnerable. Confidence in life goes away quickly but comes back slowly. "Koscielny was the central one, pulling the strings with us both and telling us where to go and that, so with someone like him and his experience it makes it a lot more comfortable".
The win should boost Arsenal's confidence somewhat going into this weekend's FA Cup semi-final against Manchester City, and kept their hopes alive of climbing back into the Premier League's top four. It gave the opponents more of the ball.
"I felt there was nervousness there in the way we played here".
Asked if the reluctance of Sanchez and Özil to sign new contracts had affected Arsenal's form, Wenger gave a cryptic reply. We were a bit over cautious in situations.
"We needed to play forward a little bit earlier, and I thought we did that, and when we scored the goal I thought we would start to put them under pressure".
"We needed to take responsibility for that and we've done that this week between ourselves".
"I couldn't be any more proud of the players".
Agnew said: "This group doesn't know how to give in, they will never, ever stop".