For this discussion I decided to breakdown the top 3 teams (Chelsea, Man. City, Man. Utd.) based on defense, midfield and offence to determine which team, as of today, is stronger for the beginning of the season. Im just going to comment about each starting XI* (with one or two replacements per section) piece by piece on the strengths and weaknesses in each section of the pitch and end up letting you know who is the strongest in my opinion.

*It is based on a 4 3 3 formation, fictional but to compare starters and possible replacements. More like an individual comparison.

lets start from the bottom...

Defense

Manchester United:

De Gea
Rafael/Jones
Vidic
Ferdinand
Evra

Very strong defense in my opinion, probably the most solid one in the league. The thing is that it is a very veteran defense with Evra and Ferdinand being kind of old right now and not on their prime; then having Vidic who is not that young and has a tendency to get injured all the time but when playing he is key for the team. And finally De gea and Rafael who are young but not yet consolidated in the team, so lets hope this is their season to shine and prove themselves worthy of a club like Manchester United.
-Jones is the probable replacement for rafael and any of the CBs in case of an injury. I have really big hopes for this guy because you can see he is very determined while playing despite not being very consistent.

Manchester City:

Hart
Zabaleta
Nastasic/Lescot
Kompany
Clichy

This is a defense that has had a lot of changes the past years, compared to the other two on this list Man. City hasnt been consistent with their defense starting XI untill the end of last season. I think they finally found what they could call their definate starting defense because Nastasic is one of the best if not the best young defender in the world. Kompany is one of the best defenders in the league and the leader of the team. Now, City could perfectly have the best offensive left and right backs with Clichy and Zabaleta assisting and even scoring a lot last season. Finally Hart did not do as well as expected last season but he is just an amazing keeper and one of the best players City has atm. He really can be a game changer.
-Lescot wont have much participation if Nastasic keeps in top form. I think Lescot should be given the chance, he is a decent defender who can still complement perfectly in defense.

Chelsea:

Cech
Ivanovic/Aspilicueta
Luiz
Terry/Cahill
Cole

Mourinho count be happier with this kind of players to work out on defense. Player by player, individually, this is the best defense in the league and also in one of the top defenses in the world. We have Luiz, who was one of the best defenders in the world last season and who can also play as defensive midfielder. The Terry who's form never seem to decrease despite his age and also being the captain of the team. Chelse has very consistent right and left backs who are the strongest defensively. There is a perfect age combination between them to keep experience and young blood balanced in defensive roles. Last but not least is Cech, simply the best keeper in the league, having him in good form is very important for Chelsea's performance along the season. Count be better defensively for the start of the season.
-About Cahill, I dont have much to say, he is young and determined to be the replacement for Terry if he ever retires. Cahill is very inconsistent when playing for chelsea but has had some amazing games like in UCL 11-12. Chelsea has even got Aspilicueta who can play both sides of the pitch as a very nice replacement.

No doubt for me, Chelsea has the best defense for this season... Then United and lastly City but only because of consistency.

Midfield

Manchester United:

Carrick
Cleverly/Anderson
Kagawa/Giggs

United has been struggling to find a permanent positions and player for their midfield. Carrick being one of the best midfielders last season and probably the best United player in the only one with a permanent spot in the team because of his fine passing and great defensive work. Cleverly and kagawa are two players who everyone is aware of as a threat in offense but not that much defensive work is being displayed by them and given the position of central midfielder they are supposed to play in the team then they are not fullfiling their respective expectations. We need Felaini so badly!
-Next we have Giggs who can play left or even central midfielder, he has permanent class with ball controll and passing but his age is preventing him to shine in every single game as he should. and now we have Anderson... What can we say about a player we've been waiting for 4 seasons to shine as he was expected to. It is the same for Liverpool fans to say this is their season as for Anderson to say this is his season. Hope both can improve significantly as we know they could.

Manchester City:

Toure/Garcia
Silva
Fernandinho/Nasri

At first sight we can see five amazing players in a team's midfield but trought last two seasons City has been having trouble accommodating them in order to take the best out of them. Toure, one of the best defensive midfielders in the world and the best player at City, No Yaya no party, enough said... Silva is a great link with the attackers, hi is a great player if you are looking for phenomenal assists and lots of forward approaches. A player any team in the world would wish to have. And about fernandinho I have very little information, I have not seen him play for city but in Shakhtar he was decent, I think we wont be able to adapt that quickly to the EPL and he will eventually start games as a sub.
-Garcia hasnt been as essential for City as he should be and I think he should be in the starting XI, he is a great defensive midfielder who can help all around the pitch. And finnaly Nasri... well, I think it is as probably for him to recover his top form as for Anderson to shine this season. If Nasari played as he did for Arsenal then United is going to have a big problem this year.

Chelsea

Lampard/Mikel
Ramirez/Ginkel
Oscar

Lampard has always been between the greatest midfielders in the EPL but I am not sure how long is he going to stay playing decently. Ramirez would be a key player for this Chelsea and I believe Mourinho would know how to use him in all his potential. He is a big threat in attack while also doing recovering work nicely. Oscar is a young star who is set to have the season of his life, he has to gain a little more experience to keep playing consistently as well as he can. If them 3 play in top form then Chelsea can be a very serious contender for the tittle.
Mikel is a player who I never really thought of as a top class player, and also I don't think he is worthy of a starting role in the team but as a sub he can be very usefull. Ginkel is a mistery for me, but I saw him playing in preseason and he was doing great.

In terms of midfield City probably has a slight edge over Chelsea, and United last of the three...
...consistency is the key to success.

Offense

Manchester United:

Van Persie
Rooney/Nani
Wellbeck/Hernandez

Almost like a dream team offense, Man Utd's forward part of the pitch should remain untouched because it is probably the only section that doesnt need any modifications or signings. Although managing this bunch of top players is not that easy and who to play is a hard choice that got Rooney very upset last season. Van Persie is simply top class and the latest top goalscorer in the EPL, he is vital for United this season as well because we depend on him being the targetman who leads the team with lots of goals. Now Rooney could be the difference between an early UCL departure and a decent run in the competition, he can be the diference between second and first place in the league. I dont want him to go at all, he is as important for this team as RVP, he just needs to get back on track because he is always there whenever we need him the most. Lastly Wellbeck has to finnaly shine as expected this season because his potential is enormous and he can become a regular first team player.
Hernandez is a player who saved United when comming out as a sub but never did much when starting the game, he needs to change that to become a top striker for the team but I think it is better to keep him as our super sub. Lastly we have Nani which is a player I have high expectations for this season, hoping for him to play as the awsome winger he is.

Manchester City:

Aguero/Dzeko
Navas
Jovetic/Negredo

City has been very active on signings for this start of the season and they seem to have very promising. Aguero is a player everyone knows what he is able to do with the ball, an absolute poacher that can also create dangerous goal occasions. He is unmovable in the starting XI for City. Now one of the nicest transfers there is Navas who would most likely start games for the team giving them an explosive wing play to expand their depth in the pitch. He is going to be a crucial player, remember my words. And in the other hand there is Jovetic who I think wont really adapt to EPL or City's team play and would have a hard time fitting in the starting team because he has Dzeko and Negredo in his way. But dont get me wrong, Jovetic is a fantastic player, I just dont see him meeting everyone's expectations as the young striker he is.
In Offense I believe City has one extra player, one that is going to be attached to the bench most of the season and it would probably come out of this two guys. Negredo and Dzeko would have to fight for that super sub spot. Dzeko proved already he can manage that task very well but Negredo is a very complete forward who can surprise many people.

Chelsea:

Torres/Lukaku
Mata
Hazard/De Bruyne

Little by little Chelsea managed to get very talented players to fit in their offense but they may just have a little issue with the targetman stricker. Torres has had lots of poor performances and by now has probably lost his starting spot to Lukaku who did very well on loan last season but is still unknown if he will do well now playing for Chelsea. Mata is the best assisting players for goals and I included him in offense because he is usually the one with the ball control in the last part of the pitch doing sensational passes for goal or ending the play himself. Mata in form is the difference between winning everything and ending up as last season. Hazard is the other key player with an amazing potential not yet reached. His wingplay is by far the best of the league and his individual skills have always given Chelsea tight game wins.
As I said before Lukaku is set to be the regular striker but people is not sure if he can do the job he is intended to while Torres is slowly gaining confidence again. And finally, De Bruyne is one of the players I want to see the most this season, he could easily get a starting place in the team because he has being doing very well in preseason and on previous loans. I know Mourinho would know how to get the best out of him.

I definitely have to give the best offense to Manchester United because they have got the best striker in the league and what seems as a perfect balance in the players set to start in the forward line, with good alternatives in the bench. 2nd place would go for City and 3rd for Chelsea just because I dont trust either Lukaku or Torres up front although the rest of the forward line is very equal.

Overall it is impossible to decide right now, I hope United can do better than last season and come back with more trophies for this season.

I was supposed to post this thread some days ago but as you can see it took some work in order to finish this as complete as I could.

Now I expect you to tell me what you think about it, my predictions and stuff I said about each team's specific area. Who do you see as the best in each area and in overall.

Also if you think any other team has a better defense, midfield or attack than any of this teams then let please comment about it and argument why.

If you want to correct me if Im wrong in anything I said please do so :)

I find it a little hard to believe that Chelsea has one of the "best" defenses in the world, because I think that Cech is the one person keeping them in line most of the time.

Also, Negredo is not very complete of a forward at all. He can head, shoot, and poach, but he lacks speed. He is pathetically slow. I'm not sure if he can succeed in the EPL's fast build-ups or not.

But nice work. I don't agree with everything you say, but the effort you put into this post was nice to see.

I agree that Chelsea need some serious work, still, in defense to make the claim that they're world class in that department.

I believe United's midfield needs some work. They lack creativity from the midfield.

I think people are underestimating Chelsea's squad.

For the defense we have Kalas and Azpi as RB. Also, Kalas can play as CB. Then our two best center-backs are Ivanovic and Luiz who in my opinion are in the top 15 best center backs in the world currently. And just in case one of them gets injured, we have the well experienced Terry and Cahill, who when on form is immense. And as LB we have Cole who is always consistent and his successor Bertrand, who has really come into his own at Cobham. Also, Azpi can be a LB if its an emergency. Not to mention Ake who is good for us in his cameos and few starts. And of course, there is Cech; one of the top 5 best keepers in the world.

Then for the midfield we have Ramires, Essien (who is improving since his spell at Madrid), Lampard who seems to never age, Mikel who is defensively fit, Van Ginkel who is like Ballack, and De Bruyne who can also play as CM. A lot of good defensive and creative players in the midfield there.

As for the front, we have Mata, Schurrle, Hazard, De Bruyne, Oscar, and Moses. In my opinion the most creative front in the Premier League. The only issue we have is the strikers. Torres is not as good as he used to be, Lukaku needs to improve a bit to be world class, and Ba hasn't found his form at Chelsea (yet). In my opinion if we get someone like Rooney or Eto'o then we will have the best team on paper.

@V & Tuanis +1 I couldn't have said it any better

Mourinho confirms Chelsea are still looking to add depth at striker
When asked re Rooney, Mourinho says "We will try until the last day to add a new player to the squad, a striker". "Not ethic" to name names.

Chelsea are in need of a World Class striker, we never really replaced Drogba who was world class and now we need another such as Rooney or Eto'o and then we are all set and completed! :)

Good post...

Well said Vendetta!

Dynastian98 Chelsea's defense is good. Minus that one special person.

Good post Tuanis.

^Oh come on, don't tell me your talking about Luiz! He has come a long way since his defending in 2011/12. He proved it in the Confed Cup and proved it last season too.

im jealous of Chelsea's mid and also Man City's because they have Yaya

Very good analysis Tuanis; most of the stuff is spot on. Personally, I would disagree with the Garcia/Fernandinho comparison. Fernandinho IMO, is going to be our most important midfielder this season, with Yaya attacking more freely, he will stay back and participate in all the build up play. Garcia hasn't shown any promise in almost all games I have watched him in, the pace of the PL seems too much for him.

@Ven: Azpi is a long way from being the finished article, and Cahill averages 1.2 screw-ups a game. Terry, Cole and Ivanovic are old, and Luiz is much better as a DM than a CB.

I think that compared to, say, City's defensive roster, Chelsea are pretty weak. I'd even say United are stronger. Chelsea's current strength is in that incredible midfield you have.

^ Also their flair up front with Hazard and Oscar and KDB and co. make them a big threat up front as well. Their defense is actually the poorest part of their lineup (except for Cech).

Thanks for the feedback guys. Just to make it clear my analysis was made based more on the individual part rather than the collective and based in the past couple of seasons :)

@Lod: Azpi is not in his prime yet but is already fantastic for Chelsea. He had a 82.61% tackle success rate last season in the Premier League. More than Johnson, Walker, Rafael, and the whole Chelsea defense. Just look at how immense he was for us. His defending is almsot better than every fullback in the EPL.

(0 defensive errors!)

As for Ivanovic, he is not old. The guy is still in his prime and hasn't even reached the age 30 yet. Also, Cole is 30 but is still consistent and helpful even at that age. Plus, Ivanovic can play RB which brings some versatility in the defense.

As for Cahill yeah he makes some screw-ups but he is improving and I'm sure will do much better this season. Plus, we all know how good Cahill can be when onform. He is also great in set-pieces and tackles well. Hell, even when Silva came to Milan he was no where near close to how good he is now in PSG. Hell, even Cole was making a lot of mistakes when was still playing for Arsenal.

Terry is old but it doesn't mean he can't play for us. He raises morale, leads the team, and still does a good job in defending when fit. And when tired, there is Luiz.

David Luiz... I don't know why people think he can play DM. Maybe it's because of his game vs Fulham and vs Basel where he was on form, but people don't understand how clueless he can be as a DM. He sometimes gets lost when he plays a DM and doesn't appear when the opposing team counter-attack. I hope this season finally proves once and for all that he is a CB and not a DM as many think. That's why Barcelona want him as CB, because he is one of the best.

I'll stand by my point when I say people are underestimating/underrating Chelsea's squad, specifically, the defense.

Chelsea's defense is top 5 in Europe in my opinion... They are very solid and with interesting alternatives in the bench