The world of football has already seen some big-money moves this summer as Europe’s giants flex their financial muscles, but more major talent could come onto the market as the clock ticks down to the new season.

Spanish club Real Madrid have been the main movers so far, splashing out more than €300 million (US$340 million) on new signings as manager Zinedine Zidane rebuilds after a disastrous season.

But there are some major transfers still mooted to happen as Europe’s elite look to add to their squads.

Here, RT Sport breaks down some of the biggest deals that could be on the cards.

MATTHIJS DE LIGT 

The 19-year-old Ajax skipper caught the attention of Europe with his commanding performances in his team’s sensational run to the Champions League semi-finals last season, and is certain to leave the Dutch club this summer.

The teams interested in acquiring the youngster’s services include some of the continents biggest clubs, with Real Madrid reportedly joining the chase for his signature alongside Barcelona, Manchester United and Paris Saint-Germain.

Barcelona sealed the signing of Ajax playmaker Frenkie de Jong back in January, and teammate De Ligt seemed set to join him at the Catalans.

But recent rumors claim he is now leaning towards a move to Paris, while any club securing the Dutchman’s signature will likely need to hand over a similar fee to the €75 million Barca paid for De Jong – if not more.

ANTOINE GRIEZMANN 

French World Cup winner Griezmann announced at the end of last season that he would be leaving Atletico Madrid after five years at the club.

It was widely assumed that the 28-year-old was headed to Barcelona, finally sealing a move that had been mooted several times before.

But things appear to have stalled, with the latest reports in Spain sensationally claiming that Barcelona icon Lionel Messi would rather see the return of Neymar to the Nou Camp, rather than the arrival of Griezmann. 

There are even claims that Barca could bring in Griezmann, only to immediately move him on to PSG in a deal to lure Neymar back (more on which later).

Even with the bizarre merry-go-round nature of the European transfer market at the moment, it still seems most likely that the Frenchman will get his preferred move to Barcelona – but failing that, there will be no shortage of suitors with Manchester United also said to be circling.

It’s likely that any deal for the coiffured Frenchman would see in excess of €100 million change hands.

NEYMAR

One of the biggest potential transfers this summer involves the Brazilian who smashed the market with a €222 million move to PSG two years ago.

Things have reportedly soured between the club and the Brazilian star, who spent the end of last season out injured and is currently sitting out the Copa America after suffering yet more injury woe.

PSG president Nasser al-Khelaifi recently said that he does “not want to have any celebrity behavior anymore,” widely seen as a warning to players including Neymar who have failed to deliver the European glory the cash-rich club craves.

The latest reports claim the player is so disaffected with life at PSG that is willing to force through a return to Barcelona.

PSG have offered no public indication they would be willing to part with the Brazilian forward, although the prospect of Barcelona including big-money Brazilian misfit Philippe Coutinho could sweeten a potential deal if they stump up around €100 million on top.

An even more incredible twist would see Real Madrid swoop in, and the club are reportedly prepared to offer €130 million as well as outcast Gareth Bale or the returning James Rodriguez (more on this pair below).    

KYLIAN MBAPPE 

Another PSG star at the center of fervent transfer speculation is 20-year-old forward Mbappe. The French whizzkid – who signed for PSG from Monaco for a reported €180 million – emerged from last season as the top scorer in Ligue 1 and without his credentials diminished despite Champions League disappointment.

A move from Real Madrid has been touted in the press, although it seems far less likely that PSG would be willing to sell Mbappe then they would Neymar.

If a club were to come in, it would surely take a world record fee for PSG to even countenance letting him go – although they would be extremely reluctant to do so at any price.

PAUL POGBA

Another French World Cup winner widely featured in this summer’s transfer speculation. Manchester United midfielder Pogba recently said it “could be a good time for a new challenge,” putting some of Europe’s biggest clubs on high alert.

The 26-year-old is reported to be a key target for Zidane’s Real Madrid rebuild, although the club would likely need to offload players first to cover the cost of the move, given their outlay thus far this summer.

Juventus are also believed to be keen to bring back a player who spent four years at the club before leaving for a then-world record fee of around £90 million ($114 million) three seasons ago.

Juve sporting director Fabio Paratici said at the unveiling of new manager Maurizio Sarri this week that the club “loves” Pogba, but insisted that he was still very much a Manchester United player.

READ MORE: ‘We love him’: Juventus director Paratici speaks on Pogba transfer rumors

It’s unclear how central Pogba is to United manager Ole Gunnar Solskjaer’s rebuild at Old Trafford, but it’s arguable that they could seek to cash in rather than keep a wantaway star who has largely failed to hit the heights expected when he rejoined them three years ago.

Any Pogba departure would likely command a fee in excess of €100 million.

BALE & OTHER POTENTIAL MOVES   

One imminent move will see Atletico Madrid seal the sought-after signature of 19-year-old Portuguese wonderkid Joao Felix from Benfica for around €120 million, which is expected to be confirmed in the coming days.    

Real Madrid’s James Rodriguez is currently reminding fans what he is capable of with Colombia at the Copa America, although his future at club level is very much up in the air.

The star of the 2014 World Cup disappointed at Real following his big-money move that summer, but told German giants Bayern Munich not to activate the option to buy him after his two-season loan stint at the club came to an end last season.

The 27-year-old will still feel he has plenty to offer, and Real will be keen to cash in to free up the funds. Serie A club Napoli are said to be interested, although Real will only let the player leave on a permanent deal, rather than on another loan.

Gareth Bale is another player Real have deemed surplus to requirements, but the 29-year-old Welshman is said to be determined to see out the remaining three years of his contract. His colossal salary could mean many potential suitors are put off, but like James he could be used as a sweetener in a trasfer deal. 

The same could be said of Barcelona forward Coutinho, who may be out of the Nou Camp door just 18 months after signing from Liverpool for around £150 million.

After failing to impress, Coutinho could be used by Barca as a pawn in a deal to bring in Neymar. 

In the English Premier League, Manchester City look set to pip rivals United to the signature of England and Leicester City center back Harry Maguire for a fee of around £75 million.

However, United boss Solskjaer is expected to add 21-year-old Crystal Palace right back Aaron Wan-Bissaka to his squad in the coming days for a price of around £60 million.

In Italy, the saga of Mauro Icardi at Inter Milan could finally come to an end, with recent reports suggesting that the 26-year-old forward wants to be freed from his contract so he can leave the club.