Per Mertesacker offers some insight into the two recent clean sheets.
Arsenal have now kept two pretty solid-looking clean sheets in a row against two teams that are by no means slouches in the attack: Bayern Munich and Swansea. We liked the defending against Bayern enough here, in fact, that we gave the highly prestigious Man of the Match award to Laurent Koscielny, this only a couple of weeks after the Arsenal defense was destroyed, picked over, and analyzed nearly to death by everyone.
Other than just "trying harder", though, had the team done anything out of the ordinary? Turns out, they had.
After the victory in Wales, Mertesacker revealed that in the wake of the defeat at Tottenham, the entire defence took it upon themselves to conduct an extra examination of their team-play on video. It gave them a new outlook."We do [this] before every game," he said. "But the defenders did it on our own and I think there has been quite an improvement. We saw ourselves as a unit on the television and I think it was a good thing to do..."
"Television", first of all, is the most Per Mertesacker thing to call it. It is nice to have verbal reassurance that the team is aware of their own problems (which of course they are), and the defender address some specifics:
"The most important thing we learned was to cover each other more. There were a lot of situations where there was no pressure on the ball and the back four was not prepared for any balls between us.
"We are always watching videos. That is not the point. Sometimes it is good to see situations and I think the very important scenes against Tottenham made it more clear for everyone."
The main issue lately for the Arsenal defense (as a whole team) is that the defenders play a high line without the midfield putting any pressure on the ball, and this is precisely the issue that Mertesacker identifies here. It is also a sign that of course Arsene Wenger is interested in tactics, even if at times he gets criticized for doing puzzling things or failing to adapt. But he also speaks about leaders on the pitch, and the fact that the defenders have taken it upon themselves to do this work can only be a good thing. If the back four and midfield can start talking to each other more and making sure everyone is doing their job, hopefully this run of clean sheets can continue after the international break.