In demand: 50 players who could move in the summer transfer window

With the transfer window now officially open across Europe, we take a look at 50 high-profile players that could be packing their bags this summer.

Goalkeepers

David De Gea (Manchester United)

Among many other things, the transfer window being open means Real Madrid will be sniffing around Old Trafford once again to gauge just how open Manchester United is to selling standout goalkeeper David De Gea. Maybe this time the fax machine will work properly.

Gianluigi Donnarumma (AC Milan)

The giant Italian shot-stopper, aided in no small part by his agent Mino Raiola, caused an uproar by rejecting AC Milan's (very) generous contract offer. Since then, this saga has fluctuated wildly. Only one thing is certain at this moment: Donnarumma's deal expires next summer, and that will lead the likes of Real Madrid to come knocking at Milan's door.

Honourable mention: Joe Hart (Manchester City), Wojciech Szczesny (Arsenal)

Defenders

Alex Sandro (Juventus)

Full-backs are all the rage this summer, and Juventus' excellent Brazilian, up there with compatriot Marcelo and Bayern Munich stud David Alaba as the most dominant left-backs in the game, is reportedly being eyed by Chelsea. The number is gargantuan - reports suggest a fee in excess of £60 million is being prepared - but it highlights just how vital the position is.

Benjamin Mendy (AS Monaco)

The Frenchman, built like an armoured truck with a hemi engine, is an elite crosser of the ball. His mix of attacking output and physical dominance, along with his age - he's still just 22 years old - is why Manchester City would likely need to stump up some £40 million to acquire his services.

Dani Alves (free agent)

Fresh off terminating his contract with Juventus after one season in Turin, Dani Alves seems all but certain to rekindle his love affair with former bench boss Pep Guardiola. Alves, 34, is widely expected to sign with Manchester City in the coming days.

Virgil van Dijk (Southampton)

Liverpool sensationally withdrew its interest in the smooth Dutch centre-back in order to avoid a potentially hefty penalty for tapping up the 25-year-old, but that won't stop Chelsea, or others, from trying to pry him from Southampton's grasp.

Pepe (free agent)

In typical Pepe fashion, the Portuguese made plenty of noise while storming out of Real Madrid. It's precisely the type of outburst that has come to define his career on the pitch, but even at 34, he's still a quality player who would improve many a backline. Paris Saint-Germain is reported to be in pole position for the cantankerous centre-back.

Kostas Manolas and Antonio Rudiger (Roma)

We'll present these two as a package, despite the fact that they are almost certainly going to different places. The Greek international could be joining Zenit St. Petersburg, while his German peer is reportedly on the verge of a move to Stamford Bridge. Roma needs to pay for its ambitious new stadium project, and will lean heavily on Monchi to work his transfer magic and replace the host of established talent that is on the way out of the Italian capital.

Kyle Walker (Tottenham)

Manchester City has been linked with just about every full-back you can think of - the position was the club's most glaring weakness last season, holding back Guardiola's revolution - but the most consistent name coming up is that of Kyle Walker. His relationship with Mauricio Pochettino seemed to deteriorate at the end of last season, facilitating a potential exit.

Chris Smalling (Manchester United)

The arrival of Victor Lindelof almost definitely relegates Chris Smalling to the bench, as Jose Mourinho is expected to pair the Swede with incumbent starter Eric Bailly in central defence. For someone with aspirations of being a starter for England at the 2018 World Cup, Smalling needs minutes.

Honourable mention: Theo Hernandez (Atletico Madrid), Aymeric Laporte (Athletic Bilbao), Serge Aurier (Paris Saint-Germain)

Midfielders

Marco Verratti (Paris Saint-Germain)

The key to Barcelona's midfield overhaul. The diminutive Italian is an elite passer - arguably the world's very best in his position - and though any deal would require massive expenditure, the Blaugrana need to make a splash after falling on their faces (for the most part) in last summer's window.

Naby Keita (RB Leipzig)

What happens with Naby Keita this summer will signal just how far Liverpool is willing to go to get back among England's elite. The all-action midfielder, who is Jurgen Klopp's primary target, could cost £70 million. He's worth it, and the Reds need to make a statement. Don't concede and settle for a secondary target.

Tiemoue Bakayoko (AS Monaco)

Barring some unforeseen development, Tiemoue Bakayoko will be putting his intriguing combination of tackling and dribbling skills on display alongside compatriot N'Golo Kante this coming season; the imposing French midfielder is all but certain to join Chelsea imminently.

Fabinho (AS Monaco)

Any club that captures Fabinho will not only be getting a rangy defensive midfielder who can turn defence into attack quickly, but they'll also have a versatile talent that is equally comfortable patrolling the right flank from full-back.

Nemanja Matic (Chelsea)

Even with the expected arrival of Bakayoko, reports that Chelsea is happy to ship Nemanja Matic out to Premier League rival Manchester United continue to baffle. For a club set to embark on a more rigorous, demanding season, Chelsea should be looking to enhance its squad depth, not shed it.

Philippe Coutinho (Liverpool)

Leaving Liverpool right now seems like an unwise move. The club has recently inked Mohamed Salah to bolster its attack, could be on the verge of signing Naby Keita to overhaul its midfield, and is slated for Champions League action next season. The Reds are on the up. But the allure of Barcelona is not easily ignored.

Emil Forsberg (RB Leipzig)

RB Leipzig has no desire to relinquish versatile attacking midfielder Emil Forsberg, but that won't stop other clubs from testing the German side's resolve. The creative genius crafted 19 Bundesliga assists last season, and would add a spark to any team willing to dig deep into its pocket to procure his signature.

Renato Sanches (Bayern Munich)

The arrival of rising superstar Corentin Tolisso poses yet another obstacle that Renato Sanches would need to leap over to get consistent game time at the Allianz Arena. Still only 19, he has plenty of time to develop, but another forgetful season spent languishing on the bench would be a serious concern for someone who is expected to blossom into a dominant midfield force.

James Rodriguez (Real Madrid)

Somebody please resuscitate James Rodriguez. Rotting on Real Madrid's bench last season - he wasn't even among the substitutes for the Champions League final, despite being fully fit - the Colombian playmaker needs to leave the Santiago Bernabeu to get things back on track. The 2014 World Cup feels like a very, very long time ago.

Leon Goretzka (Schalke)

A starring role with Germany at the Confederations Cup has seen Leon Goretzka shoot back up the list of prominent transfer targets. Reports suggest Bayern Munich will, incredibly, nab him on a free transfer next summer once his deal with Schalke expires.

William Carvalho (Sporting Lisbon)

A name that emerges every time the transfer window opens, the sturdy, dependable presence of William Carvalho would bolster almost any team in Europe. The Portuguese oozes composure, and while he can look cumbersome at times thanks to his sheer size and lack of raw speed, he makes up for that with positional sense and quality on the ball.

Leandro Paredes (Roma)

The teardown at Roma shows no sign of slowing down. Mohamed Salah is already gone, Antonio Rudiger and Kostas Manolas look set to follow, and Leandro Paredes, the excellent young Argentine playmaker, is reportedly on the verge of joining Zenit St. Petersburg along with his Greek teammate. The rest of Europe is missing out on a quality midfielder who, given the situation in the Italian capital, is available for a reasonable price.

Cesc Fabregas (Chelsea)

Chelsea's assist king looks set for another season as the third choice midfielder behind the undroppable N'Golo Kante and the incoming Bakayoko. He was masterful for the Blues last year, and could be once again - his skill set is a perfect complement to his more mobile midfield peers - but will he be content with another season as a super-sub?

Gylfi Sigurdsson (Swansea City)

Swansea's set-piece wizard had been linked both with a return to Tottenham - which is probably unlikely given he would be only a secondary option - and a high-priced move to Everton. Will the Icelandic star be the latest to join the Toffees' lavish new project?

Ross Barkley (Everton)

Ross Barkley might not actually be all that good, but he's young, has showed flashes of what he could be with the odd scintillating goal, and, most importantly for his transfer value, he's English. Everton is going to cash in, and some team is likely going to be left ruing an expensive mistake in judgement.

Honourable mention: Ruben Neves (FC Porto), Roque Mesa (Las Palmas)

Wingers

Ousmane Dembele (Borussia Dortmund)

Borussia Dortmund has no need to sell the French dribbling wizard, but that hasn't quelled rumours of a mammoth bid from Barcelona for the 20-year-old. The Bundesliga side beat everyone to the punch by getting the ambidextrous youngster for a paltry €15 million last year, and whenever he is sold, Dortmund will pocket a small fortune.

Thomas Lemar (AS Monaco)

Of all the superb Monaco stars who saw their stock skyrocket over the last 12 months, Thomas Lemar feels like the most criminally under-appreciated. The versatile 21-year-old would prove a fantastic signing should the likes of Tottenham or Arsenal be able to nab him.

Memphis Depay (Lyon)

The talented Dutchman recovered from a potentially disastrous spell at Manchester United when he moved to Lyon in January and tore up Ligue 1 in the second half of the season. The Red Devils have a buy-back clause on the 23-year-old. Will they exercise it?

Alex Oxlade-Chamberlain (Arsenal)

Bouncing between the wing, central midfield, and the bench, Alex Oxlade-Chamberlain is reportedly seeking assurances over his role at Arsenal before inking a new deal, which has led to suggestions that he could depart the Emirates this summer.

Anthony Martial (Manchester United)

Another young player whose progress looks to have stagnated under Jose Mourinho? Well, I never. The French winger, so electric in his first season with Manchester United, was relegated to the fringes last year under the Portuguese bench boss.

Douglas Costa (Bayern Munich)

Serge Gnabry's arrival should prove some additional competition at a club that already boasts an impressive crop of wingers. Arjen Robben is still the man, Franck Ribery commands minutes when fit, and Kingsley Coman needs playing time to continue developing. Costa's best option might be to look elsewhere.

Gerard Deulofeu (Barcelona)

Barcelona has exercised its buy-back option on the tricky Spanish winger, but it seems unlikely that Deulofeu will actually see any playing time at the Camp Nou. A permanent transfer away from the club is probably in the best interest of all parties involved.

Federico Bernardeschi (Fiorentina)

Arguably Italy's brightest young attacker, Fiorentina's most in-demand player offers classic left-footed elegance, supplementing his trickery with a pile driver for a leg that has already produced some wonderful long-range goals.

Keita Balde (Lazio)

Frightening pace paired with the ability to deliver inside the penalty area, defenders trying to slow down Keita Balde might as well be trying to catch a fly with a pair of chopsticks. The 22-year-old Senegalese international is fast and technically polished, and has reportedly caught the eye of Juventus.

Domenico Berardi (Sassuolo)

Every summer, Italian football lovers tip Domenico Berardi to make the leap from Sassuolo to one of Serie A's big boys. And yet, for one reason or another, he remains with the modest of clubs. Roma needs a winger in the wake of Mohamed Salah's aforementioned departure, and it's there that you'll find former Sassuolo boss Eusebio Di Francesco on the touchline. The fit seems too ideal. If not now for Berardi, when?

Ivan Perisic (Inter Milan)

Ivan Perisic is this summer's most likely candidate to be the subject of a massive overpay from an over-eager suitor - potentially Manchester United - as reports suggest Inter has slapped an outrageous €55-million price tag on his head. Best to just let this one go, Jose.

Riyad Mahrez (Leicester City)

Like the rest of his Leicester teammates, Riyad Mahrez crashed back down to earth in 2016-17. His dominant form during the club's historic title-winning campaign, for which he was named PFA Player of the Year, likely won't be replicated, but the slight Algerian can still offer some magic down the right wing.

Honourable mention: Julian Brandt (Bayer Leverkusen), Willian (Chelsea)

Forwards

Kylian Mbappe (AS Monaco)

The crown jewel of the transfer market. Everyone wants Kylian Mbappe this summer, and the 18-year-old phenom will almost certainly command a world-record transfer fee wherever he goes.

Alexis Sanchez (Arsenal)

Under no circumstance should Arsenal allow the relentless Chilean to leave the club for free when his contract expires next summer, and his apparent reluctance to ink a new deal looks likely to result in a transfer at some point in the next couple months. Whether that's Bayern Munich or Manchester City remains to be seen.

Alvaro Morata (Real Madrid)

Manchester United, having finally admitted defeat in the unfruitful pursuit of Antoine Griezmann, has turned its attention squarely toward the young Spaniard, who is coming off a prolific season with Real Madrid in which he did plenty of damage despite seeing limited action.

Romelu Lukaku (Everton)

The burly Belgian is among the greatest young scorers the Premier League has ever seen, and his propensity for finding the net has Chelsea looking at a potential reunion. Lukaku has admitted he already knows his next move; we all just have to wait for it.

Alexandre Lacazette (Lyon)

Atletico Madrid's transfer ban scuppered Alexandre Lacazette's desired move to the Spanish capital, and Arsenal looks set to be the prime benefactor. He won't come cheap, but his prolific scoring record with Lyon suggests he could finally be the bona fide threat up front that Arsenal has long been seeking.

Diego Costa (Chelsea)

Not in Antonio Conte's plans heading into next season, Diego Costa won't let his breakup with the fiery Italian weigh on his conscience. The prickly Spaniard is making no secrets of his desire to return to Atletico Madrid, even if that means he'll need to wait until the club's transfer ban ends in January before he can actually take to the pitch.

Pierre-Emerick Aubameyang (Borussia Dortmund)

The reigning Bundesliga scoring champion has a difficult decision on his hands. Now 28, Pierre-Emerick Aubameyang is in line for the final big payday of his career - strikers don't tend to age particularly well, so he needs to capitalise on his scoring excellence now. China is an option that would more than satisfy his monetary demands, but how heavily does the Gabonese speedster value the allure of world class football? Only he can make that decision. Tianjin Quanjian is said to be offering him a package that would pay him £26 million per season. Hard to say no to that.

Andrea Belotti (Torino)

Torino may have done itself a disservice by slapping a monstrous €100-million price tag on the Italian for any foreign clubs interested in his signature; the 23-year-old striker is very good, but he's not in that bracket quite yet. A move to a fellow Serie A side, for a reduced price, could be the more logical outcome.

Daniel Sturridge (Liverpool)

Jurgen Klopp obviously has no desire to use Daniel Sturridge, and the oft-injured English striker isn't content sitting on the bench. Something has to give. The 27-year-old's lengthy list of ailments won't make him very appealing to clubs battling for trophies, but, if they can handle his wages, mid-table Premier League sides should take the gamble.

Tammy Abraham (Chelsea)

On the back of a 23-goal season in which he tore up the Championship with Bristol City, Tammy Abraham is being tipped to get a chance to back that up with a free-scoring campaign in England's top flight. Chelsea is almost certain to loan him out - it's the Blues' way, after all - and a host of mid-table Premier League clubs would benefit from the angular attacker's services.

Kasper Dolberg (Ajax)

The lead singer of Ajax's latest crop of incredible teenage talent, the Danish striker can find the net in a variety of ways, and has some of Europe's most prestigious sides drooling over his potential. Still just 19 years old, another year in the Eredivisie might be his best option.

Sandro Ramirez (Malaga)

Everton is hot on the trail of the young Spaniard, who, despite what his hairline would suggest, is still only 21 years old. It's difficult to say Barcelona made a mistake letting any attacker go considering who already occupies those positions at the Camp Nou, but surely the Catalan side could have handled this situation better.

Zlatan Ibrahimovic (free agent)

Lions don't recover like humans. Even at 35 years old and coming off major knee surgery that could keep him out until 2018, Zlatan Ibrahimovic's pedigree will be too much for someone to turn down.

Honourable mention: Kelechi Iheanacho (Manchester City), Moussa Dembele (Celtic)

(Photos courtesy: Action Images)