1) William Carvalho (Sporting Lisbon)
United have been psyching themselves up to make an offer for over six months now, with their interest in Carvalho dating back to before Christmas, when David Moyes must have discovered the Sporting Lisbon powerhouse in his famed transfer bunker at Carrington.
It was only last season, though, that Carvalho established himself in the Sporting side, with the 22-year-old set to make his boyhood team one million euros for every first-team game he has played. The 6ft 2in Portugal international looks like a heavyweight boxer and possesses the subtlety of one, but that may be just what United need.
Louis van Gaal will inherit numerous neat and tidy passers but little physical presence and even fewer ball winners, which is exactly what Carvalho does: break up opposition attacks and pass the ball on to more technically gifted team-mates.
2) Kevin Strootman (Roma)
United turned their noses up at Strootman last summer when he joined Roma for £13.5million - half of a Fellaini. According to some reports, the Red Devils are willing to pay double that figure now.
Van Gaal is huge fan of Strootman and viewed the uncompromising 24-year-old as one of his 'big three' for the World Cup along with Robin van Persie and Arjen Robben. Then the holding midfielder tore a cruciate ligament in March, ruling him out until the autumn. This has not deterred the new United manager, though, who is said to be prepared to wait until January for his man.
In the meantime, he may not have to look far for a stop gap...
3) Nigel De Jong (AC Milan)
De Jong is hardly unique as a Dutchman being touted as a United target. Every one of the ten outfield players who Van Gaal chose to start the victories over Spain and Australia have been linked to varying degrees over recent weeks. But in De Jong's case, the rumours seem to carry with them an element of realism.
The Dutch destroyer is remembered as the thug who attempted open heart surgery on Xabi Alonso using only his studs, but so what? United could do with a little of that steel and determination - someone happy to be the nasty b*****d while the likes of Herrera, Mata, Kagawa and Rooney weave pretty patterns ahead of him.
De Jong is more than a bully, though. At 29, he offers vast experience and an intelligence to complement his dogged determination at the base of the midfield. Said to be available for less than £10million - still double what AC Milan paid Manchester City for him two years ago - Van Gaal will look upon De Jong as a cheap and trustworthy option, certainly in the short-term.
4) Sami Khedira (Real Madrid)
The Germany international has apparently been deemed surplus to requirements at Real Madrid, with United, Chelsea and Arsenal all said to be squabbling over Real's scraps.
The 27-year-old is entering the final year of his contract at the Bernabeu but that doesn't mean he will be cheap. The latest valuation appears to be around the £23million mark, but Van Gaal may look upon that as a bargain for a player as experienced, disciplined and intelligent as Khedira.
Joachim Low calls him "indispensable" but it is only because of a near-miraculous recovery from a serious knee injury that he is with the Germany squad at all at the World Cup. As a defensive midfielder, he seems to be just the type of individual the new United boss covets: a grafter who carries out his coach's instructions to the letter.
5) Arturo Vidal - (Juventus)
The Chilean is reportedly Van Gaal's number one target, but Juventus are understood to be reluctant to do business. Given the quality the all-action Chilean possesses, you can hardly blame the Old Lady for ignoring Ed Woodward's phone calls.
Vidal is now on holiday after a positive World Cup campaign, which followed a fantastic season with the Serie A winners. The 27-year-old - one of the last great box-to-boxers - scored 18 goals in 44 appearances for Juve and laid on five more.
Like the midfield greats of the Ferguson era, Bryan Robson and Roy Keane, Vidal can do it all. Away at Manchester City, he'll go as close as anyone to stopping Yaya Toure. Then, the following week when United are struggling to break down Stoke or Newcastle at home, Vidal will burst on to a loose ball and expertly beat whichever keeper stands in his way.
Van Gaal's admiration is nothing new. The coach tried to buy Vidal from Bayer Leverkusen for Bayern Munich in 2011, but he opted to join Juventus instead. The player is reported to be willing to join Van Gaal this time, but having only signed a new deal until 2017 last December, Juventus will squeeze every last penny out of United. Whatever they pay, Vidal is likely to be worth it, but whether they will be willing to match the Bianconeri's valuation remains to be seen.
Ian Watson - Follow him on Twitter