Ralf Rangnick has already outlined a defensive philosophy that he may bring to Manchester United, and it could solve their defensive instability.
Harry Maguire has been a target for much of the criticism surrounding United's defence this season and his lacklustre lunge saw him handed a second yellow card against Watford, to cap horrifying performance at Vicarage Road last week.
Michael Carrick managed to bring some stability to the defence against Villarreal, in terms of a clean sheet. but the chances opponents are creating against United remains a cause for concern. David de Gea has been very busy this season.
Rangnick could hold the key to a revolution for United with a different tactical philosophy, similar to the one that has already paid fruition for their Premier League rivals Liverpool and Chelsea.
While at one end of the pitch, the 63-year-old can bring the 'heavy-metal football' and intense pressing from the front — something that would certainly improve United — Rangnick has also offered a defensive insight that could be implemented to improve the faltering back-lline.
Speaking during a Coaches Voice presentation in September this year, Rangnick said: "Highly important is rest defence because if you play aggressive, high pressing you need to make sure the defenders no matter if you play with two or three central defenders that they make sure the only one or two players that the opponent has upfront, they're being marked.
"They have to be closely marked because those two or this one player is the only player that might be able to — if we allow them — to control the ball that we get the counter-attacking ourselves.
"This is also nothing less than a train the brain issue because it's very easy for a central defender because they don't really need to be fast, to mark when the ball at the other team's 16-yard box to mark this one or two players very closely.
"Even mark through ahead of them and the other one like a sandwich mark behind him and this is what we call rest defence and for me very important thing for me that you train this, not just tell them they should do it but train it in the sessions."
The win over Villarreal didn't just secure Champions League knockout qualification, it also illustrated the fact that United can still win games despite a slightly malfunctioning defence. But Rangnick can solve the problems at both ends.
His defensive ideology could help eradicate Maguire's tendency to lunge, over-commit or mark too tight and allow for the attacker to spin, often prompting the 28-year-old to haul the forward down — as was the case for his first booking against Watford.
Rangnick's experience working with a multitude of defenders including the likes of Ibrahima Konate or Willi Orban — two different types of defenders — could see Maguire given the defensive clarity he and United have been crying out for.
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