Manchester United's Defensive Dilemma Under Carrick
Michael Carrick stands on the brink of his first full season as Manchester United manager with a curious mix of reassurance and unease. On paper, his central defensive stable looks stacked: Leny Yoro, Ayden Heaven, Harry Maguire, Matthijs de Ligt and Lisandro Martínez. Names, reputations, medals. Enough, you might think, to sleep soundly.
He doesn’t.
Behind the scenes, there is a nagging fear that the heart of his team could yet become its soft underbelly. United have no immediate plan to recruit another centre-back unless one of the current five leaves. That might prove bold. It might also prove reckless across a season that stretches across four fronts: the Premier League, FA Cup, Carabao Cup and, for the first time in two years, the Champions League.
Carrick earned this shot. When he stepped in last January after Ruben Amorim’s sacking, United were punch-drunk and drifting. He had 17 league games, no distractions from cups, and a fractured dressing room to steady. He did it with impressive clarity. The chaos ebbed away, the mood improved, and the team became stubbornly hard to beat.
Two defeats in those 17 – both 2-1, at Newcastle and Leeds – underlined the progress. Eighteen goals conceded, seventh place secured with 32 points, nine behind third-placed Aston Villa. Respectable. More than that, it was a repair job completed under pressure.
Now comes the real examination. A full campaign, four competitions, and only 20 matches of managerial experience at this level behind him. The margin for error shrinks, the scrutiny deepens, and the questions around his central defenders grow louder.
Youthful promise, unforgiving stage
The raw materials are intriguing. Yoro is 20, Heaven just 19. Both are still filed under “potential”, but potential does not win you points away at Anfield or in the last 16 of the Champions League. They have to grow up fast.
Yoro, signed from Lille in 2024 for £52m, already has 66 appearances to his name. He is the more seasoned of the two youngsters: 6ft 3in, quick across the ground, composed on the ball. The profile is everything a modern centre-back should be. The reality, so far, has contained flashes of promise punctuated by the odd costly lapse. Two seasons in, United need more than glimpses. They need authority.
Heaven, at 6ft 2in, arrived from Arsenal in February 2025 for a nominal fee and forced his way into the side 11 times in the league last term. He brings technique, speed and a stronger frame than his age suggests. He knows his place in the hierarchy for now. “I’m young and I’ve got to be patient, especially in my position. You don’t see a lot of 19-year-olds playing week in, week out. I know it’s nothing personal. I’m waiting for my opportunity,” he said.
The opportunity will come. The question is whether he and Yoro will be ready when it does, or whether United will be asking too much, too soon.
Maguire’s know-how, Maguire’s limits
At the other end of the age spectrum stands Maguire, 33 and battle-worn. The former England defender has seen enough, done enough, and taken enough criticism to know exactly what this job entails. He still brings nous, bravery and leadership. He was a key part of the 2024 Carabao Cup triumph. He knows how to manage big occasions.
He is also one-paced, and that is the inescapable issue. In a league that stretches defenders to their physical limits, any lack of speed can be ruthlessly targeted. Maguire has already felt the sting of being left out at the highest level – omitted by Thomas Tuchel for the World Cup – and rivals will not hesitate to test his turning circle again.
Under Carrick, he would expect to start the season as first-choice, most likely alongside Martínez. On paper, that pairing offers balance: Maguire’s aerial dominance and reading of the game, Martínez’s aggression and front-foot defending. On grass, the plan depends on one thing United cannot currently count on – Martínez’s body holding together.
Martínez and De Ligt: world-class, if available
Martínez, 28, remains a talismanic figure. His performance in United’s 2-1 win over Manchester City in the 2025 FA Cup final drew a glowing verdict from Pep Guardiola, who called him “a top five centre-back in the world”. That kind of praise does not come cheaply. When fit, “The Butcher” transforms United’s backline with his intensity and courage.
But the caveat is becoming familiar. Fitness. He was forced off before half-time in Argentina’s World Cup final defeat to Spain with a muscle problem, and his availability for the season opener at Hull is still uncertain. Carrick knows what Martínez gives him. He also knows he cannot build an entire defensive strategy on a player whose body keeps interrupting the script.
Then there is De Ligt, a defender who should be in his prime at 26, yet arrives at this season as a medical question mark. He has not played since United’s 2-1 win at Crystal Palace on 30 November, a back injury eventually requiring surgery in May. After the operation, he spoke of having “done everything, pushing myself in every session and exploring every option, to get back to doing what I love, playing football.”
His CV is decorated: league titles with Ajax, Juventus and Bayern Munich. He knows what it takes to anchor a championship defence. The plan is for him to return early in the campaign. The reality is that no one at United can say with certainty how robust he will be when he does.
Put Martínez and De Ligt together, fully fit, and Carrick has a pairing to rival almost any in Europe. Factor in their recent medical records and the picture darkens.
A fragile core, a restless market
The uncertainty over De Ligt, Maguire, Martínez, Yoro and Heaven would be easier to swallow if United were aggressively reinforcing in other areas. They are not. Not yet.
Elsewhere among the elite, the money is moving. Manchester City have brought in Eliott Anderson for £116m. Chelsea have pushed the boat out for Morgan Rogers at £117m. Tottenham have gambled big on Sandro Tonali for £100m and Mateus Fernandes for £85m. These are clubs loading up for a title race and deep European runs.
United’s business looks far more cautious. The headline arrival is Youri Tielemans, 29, from Aston Villa – an intelligent, technically gifted midfielder, but not a defender and not a statement of structural change at the back. Andrey Santos, 22, comes in from Chelsea with just 11 league starts last season behind him. Useful additions, potentially. Transformative? Hardly.
There are still five weeks left in the transfer window. The landscape can shift quickly. A sale, an injury, a late opportunity, and United might yet move for another centre-back. For now, though, Carrick prepares for a season that will stretch his squad like no campaign he has managed before, with a defence that feels more like a puzzle than a platform.
He has made United harder to beat. He has calmed a club that had forgotten how to breathe. But as the Champions League anthem returns to Old Trafford and the fixtures stack up, the truth is unavoidable: unless those five centre-backs stay fit, grow up or roll back the years, this defence does not yet look built for what lies ahead.
