Borussia Dortmund defender Hummels has frequently been linked with a potential £20 million switch to Old Trafford yet, according to reports in Spain cited by The Daily Express, they look to face significant competition from La Liga with Barcelona prepared to make a move for his services.
A cultured, strong and elegant defender, Hummels has performed superbly for Borussia Dortmund and at international level with Germany in recent years, leading many to rightly regard him as one of the best centre-backs in world football.
Somewhat harshly discarded by Bayern Munich before he was really given an opportunity to establish himself, the 25-year-old has gone from strength-to-strength at Signal Iduna Park, helping Jurgen Klopp's side to two Bundesliga titles and a Champions League final with his perfect blend of brains and considerable brawn.
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Manchester United's needs
Strong domestic form - coupled with a tremendous showing at the World Cup in Brazil - has led to obvious interest from Manchester United, with new manager Louis van Gaal tasked with bolstering his defence following the losses of Rio Ferdinand and former captain Nemanja Vidic.
While Manchester United's absence from next season's Champions League initially led to many instantly dismissing the idea of Hummels moving to the Premier League, Van Gaal's imminent arrival as David Moyes' replacement appears to have strengthened fan belief that the club can still compete for world-class talent in the transfer market.
Barcelona are also on the lookout for defensive reinforcements this summer, however, with the retirement of club stalwart and captain Carles Puyol having left them somewhat short of quality options at the back.
Javier Macherano was often tasked with partnering Spanish international Gerard Pique in the heart of defence by previous boss Gerardo Martino and while that worked to a certain extent, it is obvious that successor Luis Enrique needs to address this issue as a matter of urgency.
Hummels would appear to fit the bill superbly, of course, although they appear to face quite a battle with Manchester United eager to do business and Borussia Dortmund presumably reluctant to see him follow Robert Lewandowski out of the exit door.