The Red Devils have made a great start to life under new manager Louis van Gaal, winning all of their pe-season games against LA Galaxy, Roma, Inter Milan, Real Madrid and Premier League rivals Liverpool. With a new era firmly underway, there's a renewed sense of optimism around Old Trafford, especially having made two big signings in Southampton left back Luke Shaw and Athletic Bilbao midfielder Ander Herrera.
However, the club need to push on and make more signings after the dismal David Moyes era, and van Gaal looks set to push on with new additions. Fiorentina winger Juan Cuadrado remains a top target for United, but they did miss out on Arsenal centre back Thomas Vermaelen, as the Belgian completed a £15m move to Barcelona over the weekend.
That leaves van Gaal needing to find another centre back to target, with only Phil Jones, Jonny Evans and Chris Smalling as recognised central defenders at the club. In the Dutchman's 3-4-1-2 system, he certainly needs to add more bodies – and Sporting Lisbon's Marcos Rojo could be the ideal candidate.
According to reports in Portugal, United have made a €20m (£16m) bid for Rojo, which is believed to be close to Sporting's asking price. The 24-year-old impressed for Argentina at this summer's World Cup in Brazil, and had subsequently attracted interest from the likes of Arsenal, Chelsea, Liverpool and Southampton.
Now, a move to Old Trafford could be on the cards for the former Estudiantes and Spartak Moscow man – and he could be the ideal signing. Of course, he isn't the big name like Borussia Dortmund's Mats Hummels or Roma's Mehdi Benatia, but he certainly fits what van Gaal is looking for.
The pursuit of Vermaelen may have seemed strange given that the injury-prone Belgian was third choice at Arsenal behind Laurent Koscielny and Per Mertesacker, but he had three key attributes; he was left footed, he was confident with the ball at his feet, and he could play at full back.
That was key with Bruno Martins Indi at the World Cup under van Gaal, as he would slide over to play at left back, allowing Daley Blind to push forward on to the left of midfield. Now, Rojo appears to be the perfect fit there too – he plays at centre back week in and week out for Sporting, but played at left back for Argentina.
With bags of potential too – far more than Vermaelen, for instance – Rojo has the ability to grow under van Gaal, and given his abilities defensively and going forward, he could be ideal player to come into the United back line given the responsibilities handed to defenders in van Gaal's system.