Manchester United have made a number of transfer mistakes in recent years and Real Madrid are the latest side to benefit from one of their poor decisions.
United will have been watching Madrid’s 2-1 win over Barcelona to watch Marcus Rashford in action but another former player caught the eye at the Santiago Bernabeu.
Alvaro Carreras used to be on the books at United but was sold before making a first-team appearance for the club and is now starring at left-back for Madrid.
We’ve taken a look at Carreras’ career so far and why United are regretting their decision to sell him.
Carreras at Man Utd
After deciding to leave Real Madrid at the end of the 2019/20 season, Carreras joined United as a 17-year-old and became a key player in their youth ranks.
He won the Denzil Haroun Reserve Team Player of the Year award in 2021/22, following in the footsteps of Nicky Butt, John O’Shea and Darren Fletcher.
The left-back made the first-team squad for the last four Premier League games of Ralf Rangnick’s tenure at the end of the 2021/22 season but remained an unused substitute.
He joined Championship side Preston North End on a season-long loan deal in search of regular first-team football and made 42 appearances in 2022/23, winning their Young Player of the Year award.
Carreras, then known as Alvaro Fernandez, played in United’s pre-season friendlies against Leeds United, Lyon, Athletic Bilbao and Wrexham in the summer of 2023 and registered an assist against the latter.
Despite Tyrell Malacia undergoing knee surgery and Luke Shaw sustaining a muscle injury at the start of the 2023/24 season, he didn’t make a competitive appearance under Erik ten Hag.
Instead of giving the defender a chance, they sent him on loan to Getafe and signed Sergio Reguilon from Tottenham on a season-long loan deal.
According to reports, Carreras was valued for his speed and attacking prowess, but those behind the scenes felt he needed to improve defensively.
Ten Hag also believed he was not quick enough for the Premier League, struggled against fast players and was more suited to a back-three formation.
“What message did United give me? That I should go out on loan, that Ten Hag didn’t count on me, that I should continue to gain experience, rhythm, and we’ll see what happens in the future,” Carreras told The Athletic in December 2023.
“But it’s clear that football doesn’t end at any club and that you have to keep working. My main objective is to return to United and make a place for myself there.”
Left-back remained a problem position for United throughout the 2023/24 season, with Diogo Dalot, Victor Lindelof and Sofyan Amrabat all filling in as makeshift cover.
United decided to recall Carreras in January 2024 after he made just five LaLiga starts for Granada, but his return to Manchester only lasted a few days.
He joined Benfica on another loan and they triggered their option to buy him at the end of the season, paying an initial €6million (£5.2m) plus €3million (£2.6m) in potential add-ons.
His Real Madrid performances
Carreras went from strength to strength at Benfica and Real Madrid forked €50million (£43.6m) to bring the left-back back to the Bernabeu in the summer.
He’s since established himself as one of the first names on the Madrid teamsheet under Xabi Alonso, starting 12 of their first 13 games in all competitions in 2025/26.
The 22-year-old made a brilliant goal-saving clearance in a 2-1 win over Mallorca and has been solid defensively in their back four system, proving United and Ten Hag wrong.
While he’s yet to register a goal or assist this season, his pace, directness and ability to overlap make him a constant attacking outlet for Madrid.
“I was optimistic [about his signing]. His personality and competitive nature have pleasantly surprised me,” Alonso said in September.
“He makes very few mistakes, he is very focused, he has great mental quality, great tactical and technical quality too, he is very complete. The instant impact he has had is surprising, it is fantastic news. We also have Fran [Garcia] and Ferland [Mendy] for that position, but his performance is excellent.”
The left-back had his first El Clásico at the weekend and was directly against Barcelona’s Lamine Yamal, who is widely regarded as one of the best players in the world.
He managed to nullify the threat of Yamal for the majority of the match, preventing the winger from having a single shot on target at the Bernabeu. Barcelona’s only goal came from the opposite flank as United loanee Marcus Rashford got his seventh assist of the season.
Carreras made two tackles, three clearances, three interceptions and six recoveries while also creating one chance as Madrid secured a 2-1 win to move five points clear at the top of the LaLiga table.
United’s current issues
While Carreras continues to impress at Madrid, United are left ruing their decision to sell the left-back.
Ruben Amorim replaced Ten Hag in the United dugout in November 2024 and immediately implemented his favoured 3-4-2-1 formation at Old Trafford.
He identified left-wing-back as an area to improve and signed Patrick Dorgu from Leece in the January transfer window in a deal worth up to £29.1million.
Dorgu is yet to fully convince in a United shirt and has been criticised for his attacking output, having registered just two assists in his first 29 appearances for the club.
The Denmark international has lost his place in the United side in recent weeks, starting on the bench in their wins over Sunderland, Liverpool and Brighton.
He was booked just two minutes after coming on against Brighton as he hauled down Yankuba Minteh while he was one-on-one with Senne Lammens.
While VAR looked at the incident and deemed that the caution didn’t need upgrading, the resulting free-kick saw Danny Welbeck pull one back for his side.
Dalot has started ahead of Dorgu in those last three games, but the Portugal international looks a lot better when playing on his favoured right-hand side.
Luke Shaw has previously operated at wing-back but is now a left-sided centre-back under Amorim and Tyrell Malacia hasn’t played for United in nine months.
United are now showing signs of improvement under Amorim after a difficult start to the season, but their big weak point remains the left wing-back position.
Carreras would’ve been a perfect fit under Amorim and they may now have to enter the market for another left-wing-back.
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