Our final roundup of the biggest transfer rumours ahead of the opening of the January transfer window sees plenty of entries for the likes of Chelsea, Liverpool and Barcelona—teams either struggling to make an impact in their respective leagues, or with out-of-favour players struggling to break into a successful team.

We have put together our usual list of 20 rumours from the past week that have dominated the headlines, ranking them according to the fee involved, the reputation of the buying club and the quality of the player in question.

These are rumours sourced from other outlets, not Bleacher Report's own views—so enjoy the last transfer discussion of the year and let us know whom you'd like your team to sign or sell!

20. Kylian Mbappe

AS Monaco's powerful and exciting young forward Kylian Mbappe is attracting interest from all over Europe, according to Le Journal de Dimanche (h/t Marca).

The likes of Real Madrid, Borussia Dortmund and Bayern Munich are all reportedly interested in signing the 17-year-old attacker, who has already played four times for Monaco's first team this season including twice in Ligue 1 and once in the UEFA Europa League.

Mbappe had a trial with Real Madrid at 14 before signing for Monaco and has been likened to Anthony Martial in style.

19. Ante Budimir

Arsenal's search for a striker is spanning far and wide, with St Pauli forward Ante Budimir the latest target of their admiring glances.

The Mirror's James Whaling highlighted reports in Italy, from Calciomercato, suggesting the Gunners have been watching Budimir while he has been on loan with Crotone this term, netting nine league goals in Serie B.

Meanwhile, at the same club and in the same report, there is a suggestion Mathieu Flamini will leave the Emirates Stadium club in the summer.

18. Alex Grimaldo

Barcelona B left-back Alex Grimaldo is out of contract in the summer—but he may make a move away from the club even sooner than that.

Nowhere near the first-team scene with Jordi Alba, Jeremy Mathieu and Adriano all playing in his role this season, Grimaldo is not going to renew his deal, and Portuguese outlets A Bola and Record (h/t Marca) are both reporting that Benfica are set to sign him for around €1 million.

Grimaldo has never featured for Barca's first team.

17. Barcelona Squad Players

Marca's Luis F. Rojo reported Barcelona are willing to offload at least a couple of squad members in January, with Arda Turan and Aleix Vidal set to finally be registered with the club and management keen to make other changes to ensure the team stays focused on winning more trophies.

Marc Bartra and Douglas from the defensive line are possible departures, with neither impacting this season, while young forwards Sandro Ramirez and Munir El Haddadi could also depart, at least temporarily, after neither managed to have a positive effect on the team while Lionel Messi was out injured.

A loan signing now appears the most likely in regard to inward bound deals, with financial constraints scuppering the chances of any big signing.

16. Jeremain Lens

Sunderland signed Jeremain Lens in the summer for around £8 million in what looked like a good piece of business—but with the Black Cats underperforming and the Dutch forward out of favour under Sam Allardyce, he looks on the verge of a quick exit.

The Mirror's Simon Bird reported Allardyce has said the club "will probably look at it" if Lens has an offer to move elsewhere in January after he was disciplined for refusing to take part in warm-down drills after a recent game.

Lens scored one goal and claimed two assists in his first four games this season, but he hasn't netted since early October and has not started in the last seven.

15. Marko Grujic

Liverpool look to be close to sealing a move for Serbian midfielder Marko Grujic for January, which would be Jurgen Klopp's first signing as manager.

BBC Sport reported the Reds have had an offer of £5.1 million accepted by Red Star Belgrade, which would see Grujic stay in Belgrade on loan for the rest of this season after Liverpool pay the entire fee up front before joining the Premier League team in the summer.

That news comes despite a report from Simon Jones of MailOnline suggesting Grujic's father was not in favour of the move.

14. Andy Carroll

West Ham United forward Andy Carroll is wanted by the club and not expected to leave in January despite reports to the contrary.

Manager Slaven Bilic said, per BBC Sport, Carroll is a "big weapon" who "fits into my attacking plans" and that he'd like to count on the English striker to lead the line this season.

Carroll's injury problems have restricted him to 10 league games this season, and he has scored one goal.

13. Giuseppe Rossi

Italian forward Giuseppe Rossi looks almost certain to leave Fiorentina in January, with his agent, Federico Pastorello, saying it's "99 per cent" the former Villarreal man will exit La Viola, according to Football Italia, quoting the agent from Radio Marte.

Rossi has struggled with terrible knee injuries in the recent past. He is fit again, yet he's unable to hold down a regular starting spot with his club.

He has not scored in Serie A this season and has been linked with Serie A and Premier League clubs.

12. Ayoze Perez

Newcastle United forward Ayoze Perez has claimed both Manchester United and Tottenham Hotspur are interested in signing him, talking to Radio Club Tenerife (h/t the Manchester Evening News' Samuel Luckhurst).

The Magpies forward has scored only four goals in the league this season but is highly regarded as a classy and versatile attacker, with Manchester United only having two recognised forwards and Spurs lacking even that in their squad.

Perez has suggested that despite the interest, his priority remains to play for Newcastle.

11. Ever Banega

Classy Sevilla midfielder Ever Banega is out of contract in the summer and had been expected to sign a new deal—but Juventus have entered the picture and the player is now keen to move on.

That's the word from Marca's Alberto Fernandez, who indicated Juve have already made an offer to the Argentinian playmaker to join in the summer on a free transfer. The matter could be complicated if Banega makes another 15 appearances in La Liga, which would automatically trigger a one-year renewal of his current deal.

Banega is a key player for Sevilla, helping them to retain the Europa League last season.

10. Augusto Fernandez

Argentinian midfielder Augusto Fernandez is set to move from Celta Vigo to Atletico Madrid early in the January transfer window, according to Marca's Alberto R. Barbero.

The combative holding midfielder is seen as an ideal replacement for the injured Tiago, who's out until March, and he will arrive at the Vicente Calderon for a fee of around €6 million.

Fernandez has already agreed terms on the deal and will move as soon as Celta negotiate the purchase of the remaining 50 per cent of his registration rights—held by Velez Sarsfield—and sell the entirety to Atletico thereafter.

9. Juan Iturbe

One of the most unexpected deals of the year, perhaps: Bournemouth signing Juan Iturbe from AS Roma.

The deal is set to go through in the near future, according to the Bournemouth Echo's Neil Perrett, with Iturbe initially joining on loan and with a £16 million option to make the switch permanent at the end of the campaign.

Iturbe has featured mainly as a substitute for Roma this term, scoring once in 19 games.

8. Saido Berahino

Another week, another rumour of a Tottenham Hotspur bid for Saido Berahino.

The West Bromwich Albion forward has been a target for Spurs for months, with failed bids in summer apparently not deterring the north London side from making another approach in January. An injury to Clinton N'Jie is forcing Spurs' hand in the market, with Harry Kane lacking in support or rotation alternatives.

The Guardian's Paul Doyle reported Spurs will go back in for Berahino—with a bid of less than the £23 million WBA turned down in August.

7. Marc-Andre ter Stegen

Marc-Andre ter Stegen's unhappiness at Barcelona means he could be looking for a way out of the Catalan club, with Liverpool being linked with a move for him.

The German was left out of the team as Barcelona won the FIFA Club World Cup on Dec. 20, despite being the goalkeeper in the UEFA Champions League victory that saw the team reach the Club World Cup tournament, and the Mirror's James Whaling indicated the Reds are looking to make a move for him in January as a result.

First-choice goalkeeper Simon Mignolet has made mistakes of late and missed a recent match injured—in which stand-in stopper Adam Bogdan made a serious error, costing a goal against Watford.

6. Jamie Vardy

Leicester City striker Jamie Vardy has gone from barely known Championship attacker to super-linked top-scoring international striker in no time at all, and Chelsea are the latest side linked with a January move for him.

The Foxes forward, who has 15 goals this term, is a target for Guus Hiddink, according to the Mirror's John Cross. The Dutchman, who was recently appointed interim manager for the Blues, has been given the go-ahead to spend money and rescue Chelsea's season.

Leicester top the Premier League table, while Chelsea are down in 15th.

5. Juan Mata and Ander Herrera

Spanish Manchester United pair Juan Mata and Ander Herrera are said to be ready to ask for transfers away from the club if manager Louis van Gaal remains in charge.

That's according to the Times' James Ducker (h/t Metro's Sean Kearns), with Van Gaal's team having lost their last three matches, been knocked out of the Champions League and sitting outside the top four in the league at present—despite hefty spending in the past two summers.

Jose Mourinho and Ryan Giggs are potential successors to the current United manager.

4. Jackson Martinez

Guus Hiddink is already looking to make big changes at Chelsea despite only being in place until the season's end—and the lack of attack is an area of concern.

The Telegraph is reporting Hiddink wants Atletico Madrid striker Jackson Martinez to be signed, potentially in a swap deal with former Atleti forward Diego Costa, with neither forward impressing for his side this season.

Jackson, absent recently through injury, has only scored twice in La Liga after moving from FC Porto for €30 million in the summer.

3. Alex Teixeira

Chelsea have all but made their first signing for January, according to the Mirror's Aaron Flanagan, with Alex Teixeira set to sign from Shakhtar Donetsk.

The report indicated a £30 million deal has been agreed, with the Express reporting a five-year deal is being discussed ahead of the two clubs formalising the transfer.

Guus Hiddink will not be able to play Teixeira in the Champions League but will hope the attacker can boost Chelsea's Premier League fortunes.

2. French Duo to Chelsea

Chelsea want to turn around their fortunes with a whopping double deal worth £110 million, according to French outlet BuzzSport (h/t the Daily Star), which claimed France internationals Paul Pogba and Antoine Griezmann are the main priorities for the Blues.

Pogba has been heavily linked with a move away from Juventus for well over a year and could feasibly cost close to treble figures himself, while Griezmann has shone at Atletico Madrid and would likely command a fee of at least £50 million.

The report indicated out-of-form Eden Hazard may be sold to free up funds.

1. James Rodriguez

Real Madrid attacking midfielder James Rodriguez is a big target for Manchester United, according to reports in Spain.

The Mirror's Ed Malyon reported journalist Jose Luis Sanchez as saying United are "very interested" in the Colombian on TV show El Chiringuito. The attacking midfielder is expected to cost more than the price Real paid for him less than two years ago—which was around €80 million.

James is a star at Real despite not always being fit to play under Rafa Benitez this summer, and he would represent a huge capture for United.

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