The coronavirus pandemic has made the transfer market uncertain -- and you can find out when the windows open and close here -- but here are the rumours floating around Europe's big leagues and beyond.
TOP STORY: Tottenham in talks with King
The north Londoners are looking for competition and back up for Harry Kane and despite having been linked with Callum Wilson in the past, Spurs are now turning their attentions to his Cherries strike partner King.
The Norwegian's agent is reported to have held talks with Spurs already. King has previously been linked with a move to Manchester United, but the Old Trafford side had a bid for £20 million rejected in January and he stayed put, before Bournemouth were relegated at the end of the season.
King is currently training with the Norway national team and will have to quarantine when he returns to the U.K.
22.31 BST: AC Milan appear to be making strides toward solidifying their midfield. After news emerged earlier in the day that they'd reached an agreement with Brescia for Sandro Tonali, the Rossoneri have "a real intention" to sign Lille's Boubakary Soumare, according to Le10 Sport, after the France U21 international was the subject of interest from Manchester United and Chelsea in January.
21.54 BST: Sead Kolasinac is a wanted man, it would seem. Earlier in the day we brought you news of AS Roma's interest in the 27-year-old left-back, and now Bild writes that former club Schalke 04 hope to bring him back to Gelsenkirchen, and that the Arsenal man wants to return.
21.35 BST: Zlatan Ibrahimovic has extended his contract with AC Milan by a year, the club announced on Monday. The 38-year-old striker's contract expired at the end of last season but he has signed a new deal after impressing with his performances. Read the full story.
21.17 BST: After a pair of successful loans in the Championship with Charlton Athletic and Swansea City last season, highly touted 20-year-old Chelsea midfielder Conor Gallagher has undergone a medical at Crystal Palace ahead of spending another campaign away from Stamford Bridge, the Evening Standard reports.
20.40 BST: Bayer Leverkusen have reached an agreement with AS Roma over the transfer of Patrik Schick, according to Corriere dello Sport, with the Bundesliga outfit paying €27m for the 24-year-old forward and sending a percentage of any future sale to the Italian capital.
20.16 BST: FC Dallas head coach Luchi Gonzalez said on a media call on Monday that United States right-back Reggie Cannon is finalising a move away from the MLS club, with the 22-year-old linked with Portuguese outfit Boavista.
19.53 BST: With Aleksandar Kolarov on the verge of joining Internazionale, Gazzetta dello Sport writes that AS Roma have identified Arsenal left-back Sead Kolasinac as a potential replacement. The 27-year-old Bosnia and Herzegovina international's wages of more than €3m annually could be a cause for concern, but the report suggests that the Giallorossi could get their man for as little as €5m, offsetting some of the cost spent on wages.
19.06 BST: Arsenal have announced they've terminated the contract of 31-year-old playmaker Henrikh Mkhitaryan to allow him to join AS Roma on a permanent basis after the Armenia international spent last season on loan in the Italian capital. Read the full story.
18.19 BST: Eight months after leaving Tottenham Hotspur for Internazionale, Christian Eriksen may already be leaving the San Siro, according to Corriere dello Sport. The 28-year-old is behind Marcelo Brozovic and Nicolo Barella in Antonio Conte's midfield pecking order, and with rumours gathering pace that Arturo Vidal may soon be joining the Nerazzurri, Eriksen's place in the team looks increasingly questionable. The report suggests that Inter would sell the player if they receive an offer of €50m, and that intermediaries have already begun offering the player to clubs in the Premier League.
17.32 BST: Gazzetta dello Sport reports that AC Milan have agreed a €35m deal with Brescia for 20-year-old midfield prodigy Sandro Tonali -- who had long been expected to join rivals Internazionale - and could announce the deal "in the next few hours."
16.45 BST: Calciomercato claims that Juventus are interested in signing Fiorentina forward Federico Chiesa.
Chiesa, 22, is available for around €70m this summer but Juve won't spend that much. Man United had been linked with a move for the Italian in the past but have since turned their attentions to Dortmund's Jadon Sancho.
16.23 BST: It is the transfer story that won't go away, but of all the summer sagas, Thiago Alcantara from Bayern Munich to Liverpool is the one that is least likely to happen ... for now. Mark Ogden explains.
16.03 BST: UPDATE on 13.42 - Ivan Rakitic will leave Barcelona to return to his former club Sevilla, sources have told ESPN's Moises Llorens and Alex Kirkland.
The midfielder -- who signed for Barca from Sevilla in 2014 -- has a year left on his contract at Camp Nou, but he does not form part of the plans new coach Ronald Koeman's has for next season.
Sources have told ESPN that Rakitic's agents have now agreed the terms of his departure with Barca, and he will join Sevilla for a nominal fee.
15.15 BST: Mexico international Cesar Montes has been linked with Wolves, Porto, Ajax and Valencia so far this summer and his agent stressed to ESPN that a potential deal may well be further along without the COVID-19 pandemic.
"For sure, without this COVID-19 situation, the market would be a lot more active and economically potent, and the option of Cesar to Europe would be resolved or on its way to being, always respecting Monterrey and with their consent," said Gelu Rodriguez, who wouldn't confirm which clubs have been inquiring.
Montes, 23, has stressed he'd like to play in Europe in the future and Rodriguez said the defender is "one of the most followed players outside of Europe in the big leagues here."
The centre-back came through the Monterrey youth system and has won a Liga MX title, a CONCACAF Champions League with Rayados, as well as 10 caps for Mexico. Rodriguez added that a move won't be forced through if a good enough offer doesn't come in what remains of this window, with the player content at his first club.
14.33 BST: Barcelona are keen to move on striker Luis Suarez, but could he end up joining another La Liga title chaser?
14.23 BST: Schalke want a new goalkeeper after Alexander Nubel joined Bayern Munich on a free transfer this summer and have targeted Arsenal goalkeeper Emiliano Martinez.
Sky Sports report that Martinez is keen to ensure his future at the Emirates but wants more than playing as backup to German goalkeeper Bernd Leno.
14.02 BST: Leicester City have been looking for a replacement for Ben Chilwell at left-back, after he joined Chelsea for £50m, and Sky Sports says the club "are in negotiations with Atalanta over a deal for Belgium international full-back Timothy Castagne."
13.55 BST: The Guardian is reporting that Chelsea have agreed an "initial club record fee of £72m" for Bayer Leverkusen midfielder Kai Havertz.
Sources told ESPN last week that Leverkusen were finally showing signs of budging from their £90m valuation. Chelsea submitted two offers and while they had initially hoped to land the Germany international for £70m-£75m, they will commit to paying an additional £18m in add-ons.
13.42 BST: Barcelona midfielder Ivan Rakitic is undergoing a medical at his former club Sevilla, says Marca.
The 32-year-old Croatian has been allowed to depart Camp Nou this summer and played for Sevilla from 2011-2014.
13.11 BST: Leeds United have already spent £26m on Rodrigo and now they want another...
Udinese midfielder Rodrigo de Paul would cost £31m, according to the Guardian, but Leeds are keen on the 26-year-old Argentine.
12.30 BST: Traditionally, the end of August heralds transfer deadline day in the summer window. The coronavirus pandemic has put paid to that this year, pushing the date back to Oct. 5 for most leagues, but today should originally have seen players on the move, breaking news, exciting rumours and enticing late developments. Now it's just an ordinary day like any other.
In a bid to ease the anticlimax, here's a timely run-through of some of the more notable deals to have been struck on Aug. 31 in recent years, and a brief glimpse at how they ultimately panned out for the parties involved.
12.17 BST: Bayer Leverkusen manager Peter Bosz has confirmed that Kai Havertz and Kevin Volland are no longer expected to train at the club.
Havertz is closing on a £90m move to Chelsea, while Volland is set to move to Monaco.
"Volland and the national players didn't participate today," Bosz told a news conference. "Bailey also wasn't there. [Jamaican authorities imposed a 14-day quarantine on him after he attended Usain Bolt's birthday party.]
"Unfortunately our squad isn't set yet. I don't expect Volland and Havertz to train with us again. It's possible more players will transfer. We definitely still have to add some players."
11.59 BST: Barcelona believe the only way Lionel Messi can legally leave for free is if he commits to not playing football next season, sources have told ESPN's Sam Marsden and Moises Llorens.
Barca's interpretation of a much-debated clause in Messi's deal is that he could quit the club but would have to forgo his salary for a season and could not sign for a new club until next summer, when his existing terms are due to expire anyway.
Messi is attempting to exercise a clause in the contract he signed in 2017 that allows him to leave for free at the end of each season. Sources at Barca have told ESPN that the deadline for activating the clause in order to sign for another side expired in June.
Meanwhile, reports in Spain over the weekend claimed Messi's €700m buyout clause is no longer active, causing further confusion.
11.32 BST: It's been quite a fall from grace for Arsenal midfielder Matteo Guendouzi.
Once tipped to the future of the Gunners', the 21-year-old has fallen out with new manager Mikel Arteta and looks set to leave this summer. Valencia are keen, says Super Deporte, and want him on loan with no obligation to sign him permanently.
Arsenal want around £40m to let Guendouzi leave, so they're probably not going to be interested in this one.
11.19 BST: Napoli chairman Aurelio De Laurentiis was asked about midfielder Allan's future, with Everton closing on a move and CalcioNapoli24 quote him as saying: "We are at the final farewell. He will go to Everton."
Real Madrid and Everton are in talks over a fee for James Rodriguez, sources have confirmed to ESPN's Rodrigo Faez and Alex Kirkland, with the midfielder having already agreed a three-year contract at Goodison Park.
Madrid are asking for at least €25m for the Colombia international, while Everton want to pay less, believing a lower fee would be appropriate given the current state of the transfer market.
After closing on a €45m deal to make Ajax midfielder Donny van de Beek his first major signing this summer, sources said that Solskjaer is now prioritising the addition of a top quality centre-back to play alongside captain Harry Maguire and Leipzig's Upamecano is the Norwegian's main target.
The 21-year-old impressed during Leipzig's run to the Champions League semifinals in Lisbon earlier this month having just signed an extension to his contract at the German club until June 2023.
The Frenchman had been due to be out of contract next June -- a deal which included a €60m release clause -- but despite committing his future to Julien Nagelsmann's team, reports in Germany claim that the new deal includes a release clause of €42m, which can be triggered at the end of the 2020-21 season.
The 23-year-old made 30 appearances for Roma last season and Diawara's agent, Daniele Piraino, told Tuttomercatoweb: "He is concentrated on his career. Diawara is at a top club like Roma, where he is happy, as there is enthusiasm around the new owners. However, he is also liked by many clubs in England, including Arsenal.
"Being linked with certain clubs is pleasing for him, as these are prestigious sides. Amadou is concentrated on football and his career."
Grealish, 24, has been on United's radar for some time and is valued at £80m. Villa won't get that much for the midfielder but are working on reducing their demands as they seek more depth in attacking areas ahead of next season.
08.50 BST: Chelsea goalkeeper Kepa Arrizabalaga wants to fight for his Chelsea place, says the Sun.
Kepa, 25, cos the Blues £71.6m in 2018 to become the world's most expensive goalkeeper but has struggled with his form this season and was dropped for the Champions League clash at Bayern Munich and the FA Cup final against Arsenal.
Chelsea have been linked with a host of goalkeepers, including Rennes' Edouard Mendy, Atletico Madrid's Jan Oblak and Milan's Gianluigi Donnarumma, but Kepa is now "impressed by the club's defensive strengthening recently" and happy to stay.
The Spaniard has four years left on his contract and is valued at £50m, with few clubs showing an interest in signing him this summer.
The Barca players were due in for coronavirus tests on Sunday ahead of Monday's first training session since Ronald Koeman was appointed as coach. Messi was due at 10:15 a.m. CET but did not show up. Sources had told ESPN that Messi planned to skip Sunday's meeting.
Messi, 33, has been advised by his legal team that taking part in preseason for the 2020-21 campaign would compromise the claim that he was able leave for free at the end of 2019-20.
The Catalan club say the clause expired in June and any club that wants to sign Messi will have to pay his €700m release clause -- although reports in the local media now suggest that clause may not be active in the final year of his deal. His contract, signed in 2017, expires next summer.
Messi and Barca are now facing the possibility of a legal standoff over the clause as he continues to insist that he is free to quit the Camp Nou this summer.
08.00 BST: Manchester United have agreed on a fee with Ajax for midfielder Donny van de Beek, sources have told ESPN's Rob Dawson.
An agreement is in place for the 23-year-old to move to Old Trafford for around €45m.
United are set to discuss personal terms with Van de Beek before the Netherlands international undergoes a medical ahead of the transfer.
PAPER TALK (by Nick Judd)
Koulibaly close to City move
The Senegal defender has been linked with every major European club in the last few transfer windows, but is reported to be keen to help facilitate a move to the Premier League.
The sticking point would appear to be the €70m transfer fee, which City believe to be too high.
Koulibaly is reportedly taking it upon himself to ask Napoli club officials to lower their price demands, though it is unclear whether they'll let him go at a reduced price.
Chelsea close in on Havertz
The German publication have stated that the attacking midfielder has been edging towards a move to west London for the last 48 hours, but that the moved has taken another step forward as a result of the 21-year-old not taking part in Bayer Leverkusen's performance tests over the weekend. And though he completed the club's coronavirus tests on Friday and Saturday, which he needed to do anyway in order to represent Germany, he could by revealed the Blues this week in a move believed to be in the region of £90m.
Havertz's Germany teammate Timo Werner has already moved to Stamford Bridge as Frank Lampard continues to rebuild his side this summer.
Sarr could move to Leverkusen on loan in an effort to help Chelsea secure the signing of Havertz.
- West Brom are close to signing Wigan and former Leicester City centre-back Cedric Kipre for £900k, who is reportedly turning down a move to Blackburn Rovers to play in the Premier League, according to the Daily Mail. Albion are also considering loan moves for Watford's Troy Deeney and Brighton & Hove Albion's Shane Duffy. Wigan, meanwhile, are desperate to raise funds after having been plunged into administration.
- Internazionale boss Antonio Conte is looking to celebrate his new extended deal as coach by landing N'Golo Kante from Chelsea, according to Football Italia. Conte is hoping to land the French World Cup winner for €55m as he looks to add experience to his Nerazzurri squad. Conte signed Kante while managing Chelsea from Leicester City in 2016 for €36m and now that Kante appears to have fallen down the pecking order at Stamford Bridge, he could be allowed to leave at the right price, particularly as the Blues look to continue their spending spree this week with the signing of Havertz.