Meh, Arsenal's defence is better than Utd's, because of one statistic, realistically..... no, just no.
We're basing it on the games up till now because.... it helps the argument? how about after each team has played each team twice and a fair comparison can be made? If we aren't talking about May, but talking about now, why from the start of august, what about the calendar year, how are Arsenal vs Utd in that sense?
Anyway I don't care about either, statistically(and subjectively) opta are saying the league average for goals conceded through individual errors(ie huge single errors that lead directly to a goal rather than simple good play from the opposition) is 22% of goals, Arsenals is 63% and just ridiculously embarrassingly poor, we've a joke of a defence, but in Arteta(until recently) and Wilshire we have some solid defensive cover that Utd don't have anywhere to be seen in their team.
When and how are Utd/Arsenal conceding their goals? Its widely agreed by EVERYONE that Utd are playing WELL below what that team has previously, and more to the point everyone is saying they are just not turning on before they go behind. So they are conceding, yes, they are conceding loads, sure, is it individual defensive errors, or the team being poor, more the latter. The team just isn't getting going until the second halves of games.
Are Utd playing at their best, not even close, is their defence capable of playing significantly better, yes. Now lets look at Arsenal, is our defence capable of playing much better? Are we widely regarded as just not bothering till half way through games, no, we fairly recently bought two of our central midfielders and they are a frequent, practiced partnership. Utd on the other hand haven't bought a central midfielder in ages, have two that should have long since retired, change who plays in midfield just about every game. Now, is that their own fault, massive managerial mistakes, yes, but is it also massively contributing to their "defensive" solidity, also yes.
Was our defence better last year, the year before, the year before that... etc.
Utd's defence has been significantly better than Arsenal's for the past 6-7 years at least, is there a ridiculously high chance that come the end of the season, the two same defences, after having played the same teams that Utd will have conceded more than Arsenal.... not really.
Utd have a significantly worsening defence though, Vidic was always over rated, but now is also becoming a sicknote, Ferdinand has been a sicknote for years, but is now also becoming a much worse defender... which would be fine if Jones or Smalling had both, progressed and both weren't ridiculously injury prone. Fullbacks, Rafael has surprisingly looked better, but then also put in one of the worst performances of the year as well(as has his brother at QPR
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), Buttner, undecided, Evra, crap and still declining.
Utd need some fixing long term, but have had worse injuries, aging players in defence and in crucial midfield positions, and still don't commit anywhere near the individual defensive errors that we have. I can however see Utd's defence being as bad as ours long term if they continue playing as rubbish as they have and keep declining as they have been. Both are fairly easy to fix though, a solid central midfield partnership, and getting some of their CB's fit for more than a few games at a time.