Barring Manchester City's £28million acquisition of Wilfried Bony, the Premier League has remained fairly quiet this month, with the majority of clubs seemingly preferring not to do their transfer business mid-season.

There's still six days before the end of the January window however (deadline day coming on February 2nd) and resultantly, plenty of time remaining to land a few last-minute deals, strengthening squads for the campaign's final run in.

With that in mind, here's a list of FIVE targets known to be on Manchester United's radar that the club should wrap up transfers for within the next week if they can.

So without further ado...

MATS HUMMELS

//www.youtube.com/embed/cOlTY9h1IsA

Age: 26

Positions: Centre-back, defensive midfield

Teams: Bayern Munich, Borussia Dortmund, Germany

Honours: Bundesliga titles in 2011 and 2012, Champions League finalist 2013, World Cup 2014

Linked clubs: Arsenal and Manchester United

Likely transfer fee: £47million, according to the Express

With Arsenal on the verge of announcing a completed deal for £15million-rated Villarreal centre-back Gabriel Paulista, Real Madrid already well endowed in the centre-back department and Barcelona under a transfer embargo until 2016, Manchester United are now unopposed in their season-spanning pursuit of Borussia Dortmund defender Mats Hummels.

The German World Cup winner is considered to be one of the leading centre-halves in world football, through his blend of aerial dominance, anticipatory defending and a Franz-Beckenbaur-esque ability to instigate or join attacks from deep positions.

That makes him an ideal fit for Louis van Gaal's progressive philosophy and would certainly address the absence of quality and leadership at the heart of United's defence.

Mirror Football have speculated the Old Trafford outfit will wait until the summer to launch a bid, but with the Black Yellows stuck at second bottom in the Bundesliga, they might fancy their chances of prizing the £47million-rated centre-back away from Westfalen this week.

AYMERIC LAPORTE

//www.youtube.com/embed/vXqN7EieWVs

Age: 20

Height: 6 foot 2

Positions: Centre-Back and Left-Back

Teams: Basconia, Bilbao Athletic, Athletic Bilbao, France U21s

Honours: None

Linked clubs: Arsenal, Chelsea, Manchester United

Likely transfer fee: £32million release clause

Another centre-back known to be on the Old Trafford radar is Athletic Bilbao defender Ayermic Laporte, who has averaged the most interceptions per-match of any player in La Liga this season.

He's rated as one of the division's hottest defensive prospects, having already registered 68 league appearances for the Basque outfit and become an integral cog of their backline at just 20 years of age, demonstrating huge responsibility for a player so young.

The France U21's phenomenal athleticism, chiefly his pace and imperious leap, should serve him well in the English top flight and plenty Premier League clubs have resultantly been linked with his signature over the last few seasons.

He may not address the limit of experience and leadership in United's defence but seems like a wise enough long-term investment for the Old Trafford outfit, especially considering Louis van Gaal's exemplary record when it comes to developing young prospects.

A lot of ground has to be made between now and the end of the window to land Laporte, but with his release clause set at £32million, there's no need for lengthy negotiations with Bilbao.

That may appear a rather audacious sum, but it's still £18million less than the apparent price of fellow United target Marquinhos.

DARREN FLETCHER

//www.youtube.com/embed/geBA0Pg1XUU

Age: 30

Height: 6 foot

Positions: Central Midfield and emergency Centre-back

Teams: Manchester United, Scotland

Honours: Five Premier League titles, FA Cup 2004, Champions League 2008, PFA Team of the Year 2009/10

Linked clubs: West Ham, West Brom, Valencia and Celtic, according to Manchester Evening News

Likely transfer fee: Nothing, per MEN once again

On the outward front, it appears veteran midfielder Darren Fletcher is the most likely Manchester United player to leave Old Trafford this month, being currently in talks with four clubs regarding a winter move.

The 30 year-old is one of the most experienced members of the squad, as the only current United player to have lifted the FA Cup with the Red Devils a decade ago, and also boasts 342 appearances for the Carrington club.

But Fletcher is still someway shy of re-emerging as the shin-shattering, all-action midfielder prior to his lengthy spell away from the game due to ill-health, and has gone on to see just 365 minutes in the Premier League since Louis van Gaal's arrival in the summer. Rather tellingly, he's not started a league fixture since August.

With his contract set to expire at the end of the campaign anyway, the Scottish enforcer will be leaving United on a free transfer according to reports this morning, which also moot West Ham as his likeliest next club.

NATHANIEL CLYNE

//www.youtube.com/embed/gmdDXY-OgbE

Age: 23

Height: 5 foot 9

Positions: Right-Back

Teams: Crystal Palace, Southampton, England

Honours: Crystal Palace Young Player of the Year 2009 and 2010, Football League Young Player of the Year 2010, Crystal Palace Player of the Year 2011, Championship Team of the Year 2011/12

Interested clubs: Manchester United, according to The Express

Likely transfer fee: £20million, according to The Daily Star

Constantly fluctuating between back fours, back threes, midfielder-come-defender Antonio Valencia and unfit Brazilian Rafael, who actually constitutes Manchester United's first choice right-back at this moment in time remains open to interpretation.

Resultantly, It's believed Louis van Gaal is in the market for a new No.2, with his priority choice this window being Southampton star Nathaniel Clyne - whose performances over the last 18 months have propelled him to the forefront of the England team.

Indeed, the 23 year-old's contribution to the Saints' rise to third-place this term has been exemplary, averaging the most tackles per match of any Premier League player, 4.2, and netting twice in twenty league appearances - including an absolute stunner against Aston Villa in November.

He and Luke Shaw developed a telepathic understanding on opposing flanks at St. Mary's last season and if Louis van Gaal can rekindle it at Old Trafford, there will be a new sense of fluidity and structure to United's defence.

That makes Clyne's £20million valuation seem like a worthwhile investment, despite his contract now entering its final 18 months, but conflicting reports from the Daily Mail claim he won't make a decision on his future until April, delaying any potential deal until the summer.

SAMI KHEDIRA

//www.youtube.com/embed/RetIjHKY6pA

Age: 27

Positions: Central Midfield

Teams: Stuttgart, Real Madrid, German National Team

Honours: Bundesliga title 2006/07, La Liga title 2011/12, Copa Del Rey 2010/11, 2013/14, Champions League title 2013/14, World Cup 2014

Interested clubs: Manchester United, Arsenal, Chelsea and PSG, according to the Daily Star

Likely transfer fee: €18million, according to Inside Spanish Football

With his contract set to expire at the end of the season and a new deal yet to materialise, it would be incredibly surprising if one of Europe's top clubs didn't attempt to lure Sami Khedira away from Real Madrid before the end of the transfer window.

Manchester United's engine room lacks balance and the German international could well be the perfect remedy, as a dynamic box-to-box with ruthless energy, fantastic defensive awareness and imperious ability in the air.

His quality and experience remains undoubted, having won both a Champions League title and a World Cup during the summer, but recurring injury problems could be a major turn off for the Red Devils; prolonged sideline bouts has resulted in Khedira making just 21 league appearances over the last 18 months.

Nevertheless, €18million is a more than acceptable fee for such an established and proven centre-mid.