Manchester United have had undoubtedly their worst season for the past two decades, not good enough to be even involved in the UEFA Champions League after 20 years in the competition.

Now into the quarter-finals of this year's World Cup, are three any stars that may have emerged from their respective groups to impress new Man United manager Louis van Gaal to go in for a purchase?

From group F, only Argentina advanced to the last eight, but on the way a few players did manage to capture the limelight before being sent home.

Here are SIX WORLD CUP STARS Manchester United should sign from Group F.

Ricky Alvarez

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Angel Di Maria

Angel di Maria

Age: 26

Club: Real Madrid

Position: LW, RW

Nationality: Argentina

Estimated Value: £25million

Despite his regular starts and impressive displays for both Argentina and Real Madrid, Angel di Maria is still not as highly valued compared to the likes of Gareth Bale and Cristiano Ronaldo. He was the best player during last season’s Champions League final, and with Bayern’s Toni Kroos set for a move to Madrid, could be ready to leave.

However the Argentine will not come cheap, approximately costing no less than £25million to lure the winger to Old Trafford. Yet with already £55million spent on Ander Herrera and Luke Shaw – and another estimated £150million left of transfer kitty – £25million will be peanuts.

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Javier Mascherano

Javier Mascherano

Age: 30

Club: Barcelona

Position: CB, CDM, CM

Nationality: Argentina

Estimated Value: £14million

Louis Van Gaal’s main priority will be to add quality in the United midfield and defence, and should really consider Barcelona midfielder Javier Masherano as the man to do so.

The Argentine is naturally a defensive midfielder, but has been effectively deployed as a centre-back by both his national team and the Catalan giants. A player with this skill and versatility will do well in the Dutch manager’s attempt to get used to the Premier League.

Miralem Pjanic

Pjanic

Age: 24

Club: AS Roma

Position: CM

Nationality: Bosnia-Herzegovina

Estimated Value: £18million

Already a former Manchester United target, Pjanic became one of Serie A’s best midfielders playing a pivotal role in Roma’s second place finish last season. He would easily fit into the United midfield lacking creativity, with his dribbling and passing un-matched in the Red Devils’ current crop.

The Bosnian scored six goals, providing another six assists for the capital club last season. If he can get anywhere close to those numbers playing in the middle of the Old Trafford park, it would definitely be money well spent by the Dutch manager. A Herrera-Pjanic central midfield would look frightening on paper.

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Ricardo Alvarez

Ricardo Alvarez (Argentina):

Age: 26

Club: Inter Milan

Position: CM, AM

Nationality: Argentina

Estimated Value: £14million

Another Argentinian that should be on the United target list is Inter Milan’s Ricardo Alvarez. Labelled as the next ‘Ricky Kaka’, Alvarez was one of the few stars in Inter’s rather disappointing campaign last season.

However the 26-year-old is quick on the ball, able to take on his marker as well as supplying a key pass during an attack. Alvarez is also extremely hard-working, contributing to the team’s defensive duties with an average 2.5 tackles per game. And although he was deployed in the middle by Walter Mazzarri, Alvarez is extremely capable of playing the wings in the case that Juan Mata or Januzaj is injured.

Ogenyi Onazi

Ogenyi Onazi

Age: 23

Club: Lazio

Position: CM

Nationality: Nigeria

Estimated Value: £6million

Manchester United are currently linked with a few high profile defensive midfielders, such as Arturo Vidal and Nigel de Jong. But Louis van Gaal should really consider Nigeria’s Ogenyi Onazi, whose skill-set fits their criteria perfectly.

Onazi is a ball-tackling midfielder that is reliable in possession, able to link defence into attack. The Nigerian is the perfect anchor to a more attacking minded central midfielder, which could allow Ander Herrera to have free reign to do his intricate passing further up the pitch.

Onazi is also only 23 years of age, and with the right coaching and guidance, could anchor Man United’s midfield for several years.

Federico Fernandez

Federico Fernandez

Age: 25

Club: Napoli

Position: CB

Nationality: Argentina

Estimated Value: £5million

If United are looking for a towering defensive replacement to Rio Ferdinand and Nemanja Vidic, they should consider Argentine centre-back Federico Fernandez.

A somewhat surprise pick for Argentina’s World Cup squad, Fernandez was however essential to Napoli’s third place Serie A finish last season. Even if Fernandez was not to be Van Gaal’s marquee defensive signing, he would definitely add depth in United’s quest to challenge in the domestic cups and would only cost around £5million.