Arsene Wenger picked the same team as the one which beat Liverpool and I was surprised to see Kieran Gibbs playing after he went off injured on Saturday. It was a strong looking Arsenal team but I was worried they had so few attacking options on the bench because of the current injury problems.
Dortmund looked to hit Arsenal early as they came out of the traps quickly, but they didn't really create too much. In a pretty tame first half they had one really good chance but thankfully it was put wide by Henrikh Mkhitaryan when he really should have scored. For their part Arsenal didn't manage a single effort on goal as their attacks constantly broke down in the final third. The most worrying thing in the first half was the yellow card Mikael Arteta picked up and he walked a tightrope for the rest of the game.
The second half started with Dortmund throwing the kitchen sink at Arsenal and Arsenal struggling to keep them out. A goal for Dortmund seemed almost inevitable but a combination of good defending and goalkeeping kept them out until Arsenal gradually came back into the game. They still hadn't managed an attempt on target but that changed dramatically after 62 minutes.
Tomas Rosicky lost possession but won it back again quickly and played a pass out wide to Mesut Ozil on the right. He chipped the ball to the far post where Olivier Giroud rose to head it into the path of Aaron Ramsey just four yards out. Ramsey headed home despite a foot raised very close to his face and having his shirt pulled and Arsenal had the breakthrough goal they craved.
The game opened up very quickly and it was end to end stuff with chances to both teams. Ramsey almost scored again and Per Mertesacker came very close from a set piece after beating the keeper to the ball. At the other end Dortmund came close a couple of times but the better chances came Arsenal's way. As the clock ticked by Arsenal looked more and more capable of holding on to their lead.
They eventually managed to see the game out but there was a little controversy before the end when Mertesacker seemed to impede Robert Lewandowski as he tried to score an equaliser. The referee could possibly have given a penalty but the same could have been said for challenge by the Dortmund keeper which took Laurent Koscielny out without getting the ball. From an Arsenal corner in the first half both Giroud and Mertesacker had their shirts clearly pulled but again the referee chose to ignore it.
Lewandowski really shouldn't have been on the pitch at that stage anyway as he had already picked up a yellow card when the referee chose to ignore a dive by him in the Arsenal box. Not only did he dive but he dived into Arteta in an attempt to get him sent off for a second yellow card.
Arsenal managed to hold out and complete their second victory of the week and now there's only the trip to United to come to finish it. The win puts them on top of their group with nine points from three games and in with a very good chance of making the knock out stages. If they can win their next game at home to Marseille they will be almost there but will still have a very tricky trip to Napoli to come.
It has now been more than eight months since Arsenal lost an away game and they have won away to both finalists in last season's Champions League in that run. They face a tough match away to the reigning Premier League Champions on Sunday, but confidence has to be high with their current away form.
I thought Giroud was having a very poor game by his standards until he managed to set Ramsey up for the all important goal. No matter how things were going for Giroud he never stopped trying and the team reaped the reward in the end. He will play a lot better in many other games this season but his effort can never be faulted.
There's a possibility of both Mathieu Flamini and Theo Walcott returning to the squad for Sunday's game and hopefully Jack Wilshere too. With an international break coming up after the weekend there's a possibility that Lukas Podolski and Alex Oxlade-Chamberlain will be back for the Southampton game in two and a half weeks too. This team is doing so well at the moment that the additions can surely only make it better.
Dortmund can be added to the list of clubs Arsenal have won away to in the a Champions a League under Arsene Wenger. It's a long list and contains most of the very best teams in Eurooe over 17 years. They're the opportunities you get when you play your European football on a Tuesday or Wednesday night rather than a Thursday.
I'm really looking forward to Sunday's game and I think Arsenal have a real chance of getting a very good result. If the worst were to happen though they will still be top of the table going into the international break and top of their Champions League group too. For a season in which so many experts thought they were going to struggle that's certainly a very good start.
That's it for today.
See you tomorrow.