Well I don’t think many Arsenal supporters saw that coming.

Arsenal were sensational. If we’re going to slate them for being awful when we get a poor result, we have to praise them when they get an excellent win – and that’s exactly how it was yesterday against Manchester United.

The league leaders were blown away and we fully deserved it. The team which were top of the Premier League looked completely lost as we attacked time and time again – if you wanted to be picky you could argue that Arsenal should have scored 5 or 6 goals at least.

Alexis Sanchez was, well, Alexis Sanchez. There are no more superlatives to describe the guy – he is simply outstanding and we are blessed to have him in an Arsenal shirt. He makes the extraordinary look simple and he is truly a world class player.

Mesut Özil looked excellent as well, although he had chances to score a second goal in the 90 minutes. Özil needs to put in a top class performance week in, week out, if he wants to help Arsenal win the biggest trophies. Is this his season? Only time will tell.

But the most encouraging performance for me was from Theo Walcott.

The main striker role is the position we were having the most problems with as it was clear that Olivier Giroud is good to an extent, but doesn’t perform in the biggest games and fails to make the difference when we really need him. The Monaco home game last season was a match with summed up his talent – tries hard but doesn’t have the quality to score enough goals or get us to win the big games.

But with Theo, the signs are promising.

In the last 10 seasons this is the first where Theo has been given a starting berth as Arsenal’s main man. We only have one main striker and he has been given the chance by Arsene to prove he can make it there – and at the moment, he is doing excellently.

Walcott has been criticised for not having a football brain but this season he has shown he has the ability to adapt. Already in this campaign, his hold up and link play has improved dramatically, and his football intelligence has improved ten fold.

He brings others into play, can find a decisive pass and although he didn’t score yesterday, still has an eye for goal. If you want to be super critical you could say his finishing could improve, but don’t forget he is still relatively new to the role.

Like against Leicester last week, he was excellent again against Manchester United. His link up play was good and he made two assists – one for Özil and one for Sanchez. His movement off the ball has improved a lot and his overall game is much much better than before.

He obviously has the blistering pace and the way Walcott, Sanchez and Özil were passing the ball between themselves was mesmerising at times yesterday. And if they are that impressive in early October how are they going to be once they get used to each other in a few months time?

There has to be no doubt whatsoever that Theo is Arsenal’s main man this season – and the bottom line is our title challenge this season relies on his performances.

We all know that Olivier Giroud is not good enough to lead Arsenal to a title, but with his improving performances and adaptation to the role, Theo Walcott is.

The transfer window slammed shut at 6pm today and I, like many Arsenal fans I imagine, were hoping for a miracle – hoping that Arsene Wenger could pull off a transfer deadline day deal which would improve our squad.

Unfortunately that never happened.

Arsene have stuttered badly this season, picking up 7 points from their opening 4 games. Manchester City are on fire, taking 12 points from 12 which leaves us 5 points off the pace already. Chelsea are doing even worse at present, which doesn’t lessen the poor start we’ve managed to make.

The areas we need to improve are relatively obvious. I say relatively because the vast majority of Arsenal supporters think that to be genuine title contenders, we needed to add a top goalkeeper, top central defender, top defensive midfielder and top centre forward.

For me though, all we needed to add to be real Premier League challengers (from the squad of last season) was to add a top goalkeeper and a top striker. We signed Petr Cech so to miss out on a real finisher is really frustrating.

Honestly, that’s all I think we need to be real contenders. Because hand on heart, Olivier Giroud is never going to be the man to fire us to the title – you can quote me on that.

The excuse that there are no top strikers available is absolutely ludicrous, and Arsene Wenger’s argument that none can be bought is farcical. Olivier Giroud is a limited striker who does a certain job but isn’t a top class finisher. There are top strikers all over the world, playing in leagues all over Europe – so don’t even pretend for a second a club like Arsenal couldn’t lure a decent striker for around £25 million, because if you believe Arsene Wenger then you are delusional.

The next question you’re going to ask me is “well, who could we have bought then?”. My answer to that is I’m not a well paid football scout employed by Arsenal Football Club – Arsene Wenger has a hell of a lot more information and data on players around Europe (and the world) and can make a much better judgement on strikers that I can.

But off the top of my head, how about Charlie Austin or Javier Hernandez? Would have cost £15 million or less and they have a proven goalscoring record. And they are players (unlike Giroud) who you would be confident in scoring a chance when presented to them, instead of needing 6 opportunities to score.

So far this season we’ve “scored” 3 goals in 4 games, and two of those were own goals. That means Arsenal have scored 1 goal in 4 games, which is very poor considering the number of chances we create.

Arsenal desperately needed a striker and instead of getting one, Arsene Wenger went on his jollies in Paris.

And how frustrating is that?

Arsene Wenger has been lauded as a genius for bringing in Petr Cech. Finally, Arsenal had a world class goalkeeper since the days of David Season (and Jens Lehmann of the Invincibles season). The era of Almunia, Fabianski and Szczesny making mistakes which would cost us valuable points was over.

This was a new dawn, a new chapter in Arsenal’s history.

But then Petr Cech made his debut for Arsenal and it quickly became apparent that he wasn’t the messiah, the man to come and save us.

He was actually an ageing goalkeeper who was past it and nowhere near being at the world class standard we all thought he was.

I wrote way back in June that Chelsea only sold Petr Cech because he was past it, and yet again I have been proved right when all others thought otherwise.

I hate being right all the time.

Look, everyone makes mistakes. But yesterday was an utter shambles, a disgrace and if you’re not disgusted then you just have to laugh. After debating whether Szczesny or Ospina were the better option we brought in Cech and suddenly the problem was solved and those two goalkeepers were regarded as squad players.

The fact is Arsenal are now in a worse position than they were before they signed Cech! Szczesny has moved to Italy and is on loan at AS Roma for the 2015/2016 season. Ospina is still at the club and after his performances last season you would like to see him back in the team – while unspectacular, at least he didn’t make two glaring mistakes in a single game.

The performance from Petr Cech has been played down as simply a bad day at the office. But the mistakes aren’t just mistakes. The first mistake from Cech was simple decision making. There was no way in hell he was going to win that aerial battle and he was in no mans land.

The second was amateurish and you can cover it up however you like, it was a howler of epic proportions. A nothing shot managed to go in at the near post from 20 yards out. It wasn’t struck particularly well or had so much power that Cech didn’t have a chance to react – it was a poor shot that should have been saved.

Petr Cech is a goalkeeper lacking in confidence after being on Chelsea’s bench last season and I’ve already mentioned that Jose Mourinho wouldn’t let him leave unless he thought he was past it. Yes, publicly Mourinho is always going to “oppose” his departure – he’s hardly going to give him his blessing is he? Mourinho has played the media to his tune and all the watching crowd (Arsenal fans in particular) have lapped it all up.

If Petr Cech was that good, then they wouldn’t have brought in Thibaut Courtois last season. If Petr Cech was that good they would have kept him at Chelsea (remember, no-one leaves Chelsea unless they want them to).

Is it completely outrageous to think that Arsenal have been duped? Petr Cech wants more regular football and Chelsea want a direct rival to “weaken” so what’s the ideal solution? Jose Mourinho is many things but he’s not stupid – he’s seen Petr Cech in training God knows how many times and let’s for a moment consider that he believes Cech is past it.

Selling him to club like Arsenal would be perfect – Cech gets a big new contract and is financially secure for the next 3/4 seasons, Chelsea get £11 million for a goalkeeper they consider surplus to requirements and a direct rival is weakened in a position they have never really looked strong in.

Only time will tell but before the season started the “experts” said Petr Cech was worth an extra 10/15 points to Arsenal. Well I’m not sure how true that is going to turn out to be as he’s already cost us 3 points already.