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Whether it was the pressure to perform that came first or the poor results is secondary right now to Manchester United. Both are hurting the defending champions every single week at the moment, and David Moyes' men seemingly don't have the answers to end their horror start to 2014.

Fresh off 2-1 defeats to Tottenham Hotspur and Swansea City, there might have been a bright sense of optimism as United made the trip to the Stadium of Light.

But rarely are these matches an easy fixture for the "bigger club."

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United looked to rest several of their star players (knowing that they cannot afford to lose to Swansea City on the weekend in the Premier League) while Sunderland were able to name close to a full strength team. That's not an excuse for the defending champions—not in the slightest—but it does set the platform for what would turn out to be a historic home victory for the Black Cats.

Ninety minutes later and after three set-piece goals, it would be Sunderland who emerged with a 2-1 advantage that'll they take to Old Trafford for the second leg.

Few could have predicted it; few can still hardly believe it.

So how did United deliver such a poor performance against Sunderland?

Let's break down the film and see exactly where the Red Devils went wrong, and how Moyes can correct these problems for the remainder of the season.

CM Over-Run Once More; Puts United on Back Foot

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Manchester United's problems in central midfield have been well-documented this season, but don't appear to be going away any time soon if their performance against Sunderland is to be believed.

With Marouane Fellaini injured, Tom Cleverley started in the middle alongside a less-than-healthy Michael Carrick here as United's box-to-box midfielder.

Particularly with Carrick not quite yet recovered from his earlier injuries, Cleverley was going to need to play an important role pressing forward with the ball and allowing Carrick to anchor the team—sitting just of the back four.

There was also much onus on Cleverley not to get too out of position here with a fluid forward line ahead of him as Adnan Januzaj and Ryan Giggs often interchanged, and the England international simply couldn't cope with what David Moyes asked of him.

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Look here at how deep the Englishman has dropped despite the fact that Carrick is deep—allowing Sunderland to press heavily up from midfield. Especially in attack, he needed to keep trying to get forward and allow Carrick to be the one to pick the ball up from the defense as the deep-lying man.

Together, they were like a double-pivot that didn't know their defined roles.

Individually, Cleverley was over-run going forward and struggled in defense, with his failures in the middle of the park putting United under far too much pressure.

It was Cleverley who was at fault in Fabio Borini's match-winning "penalty" on many occasions; first giving the ball underway when he wasn't under pressure, and also bringing down Adam Johnson inside the penalty area, but his biggest problem came before that poor challenge.

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After losing the ball, Cleverley opted to rush away from Carrick and try and make a one-on-one tackle, which he lost. Johnson skipped around him and was then able to drive forward at United's defense without any real pressure running forward at him for fear of giving away a needless foul.

Patrice Evra couldn't come in right away because he had a man out wide; Carrick had to hold his spot in the middle of the field alongside Steven Fletcher.

That allowed Johnson to drive right through the middle and win the penalty.

The tackle itself was a silly foul from Cleverley, but it was one that should have been avoided 10-20 seconds earlier. Had he not rushed up the field and separated himself from his midfielder partner in Carrick, he wouldn't have put United's defense under as much pressure as he did.

Having said all of that, there's a balance.

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Playing as a defensive central midfielder as part of a double-pivot means, first and foremost, that you cannot get caught out of position and dragged away from the centre of the field. But that doesn't mean that you can't apply pressure at all; Manchester City's Fernandinho is a great example of the manner in which DCMs hold their shape and then press forward at the right moment to win turnovers.

For all DCMs, the best time to apply pressure comes inside their opponents half. From United's point of view, though, such pressure was simply non-existent.

Without Wayne Rooney in the starting team, United were missing their biggest weapon in terms of pressuring defenders, and it was clear from the opening few minutes that Januzaj and Giggs (who interchanged between the left and middle in the opening half) weren't going to provide that threat.

Look at the space here that Sunderland have to clear their own end.

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By the time the pass is ready to be hit, neither Cleverley or Carrick has exerted any real pressure. They've just held their ground in the middle of the field and given the Black Cats' midfielders all the time in the world that they need to make a run and find some open space on the wings or in behind.

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What the pair should have done was either pressure Lee Cattermole much earlier, or drop back so deep that Sunderland's midfielders weren't in behind and brought Januzaj back down the field as well.

But it didn't happen, and the pressure-less defense remained.

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Part of this comes by using players different to the week before, but at the same time, this was also quite poor from both Cleverley and Januzaj in not recognising the role that Carrick (who was clearly not 100 percent) was going to play on the night, not quite his usual deep-lying but driving self. They needed to offer more pressure up the field and give Carrick space, but they didn't, and that allowed Sunderland to break into Manchester United's half with ease throughout the night.

In a game that they needed to start positive, United had less than 40 percent possession after 20 minutes—an absolutely astounding statistic indeed!

CM Struggles Put Too Much Onus on Crossing and Januzaj

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The struggles of United's midfield, though, didn't just stop and end with the middle of the park. It affected their entire production across the pitch, and against a deep-lying Sunderland team, it made them extremely vulnerable and predictable as they sought to go forward.

A great example of this came right before the end of the first half.

Januzaj picked up the ball in a great area, but Sunderland had quickly dropped plenty of men back and had their 4-3 formation well set up outside the box.

Only Antonio Valencia and Ryan Giggs presented an option.

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We'll let Danny Welbeck off the hook here given the sheer abundance of players back behind the ball, but there's simply no excuse for Cleverley and/or Carrick not to be arriving into this attack. They're too slow getting forward and that forces United into one of two options: a) letting Januzaj try and beat a man one-on-one, or b) playing the ball out wide to either Giggs or Valencia.

What this does is make United incredibly predictable and routine.

Sunderland know that the only real option Januzaj has is to shift it wide to Giggs, and they can then cover themselves for the cross to come in by taking away his back-pass to an overlapping Patrice Evra.

The cross comes in and Welbeck simply can't get there because of the number of defenders, with Vito Mannone coming easily off his line to collect the cross.

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This failure in attack might not have seemed like much, but what it did was force the Red Devils to play a predictable attacking move and allow Sunderland to win back possession. They would then launch the ball forward moments later for the first goal of the match, and wouldn't look back after that.

So yeah, it was actually a big moment after all.

How Moyes goes about fixing this issue is difficult. Does he play Anderson more, or Darren Fletcher more and allows Cleverley to rest and find his form once more?

Can he continue to play a below-healthy Carrick until Fellaini returns?

Is it time to recall Nick Powell from loan?

Is it time to splash the cash and bring a big-name CM this January?

Whatever the case, it's time for a change to take place at United in the middle of the field. They are getting crucified week in and week out by teams that have figured out the same-old system that United are trying to play (which, in their defence, has been brought about by a slew of injuries), and until they start to correct it and offer some more diversity in attack and solidity in defense, the Red Devils will struggle to threaten their opponents anywhere near what they have in years gone by.

Champions League qualification next season is looking tough as it is.

Read more in the "Film Focus" series here.

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