Borussia Dortmund forward Jadon Sancho could cost in excess of £100m
The Premier League season reached a thrilling climax just three days ago - but clubs are already switching their attention to the 2019-20 season.
The summer transfer window opens for business this Thursday, 16 May and will remain so until 8 August.
Manchester United manager Ole Gunnar Solskjaer has admitted he "need players in" after finishing sixth, 32 points behind champions Manchester City.
It's still early and most clubs are looking at many names, options and scenarios with no doubt some complications and complexities to come. Things can and do change.
But here's my guide to where the top six could make changes this transfer window.
- David Ornstein was on BBC Radio 5 live's special look ahead at potential summer transfers - listen to it here
Manchester City keen on Rodri
Rodri (left) played 46 games across all competitions for Atletico this season, scoring twice
The priorities are a 'number six' and a left-sided central defender.
Atletico Madrid's Spanish holding midfielder Rodri, 22, is among those being considered for the 'number six' role.
The aim of that signing is to produce an eventual successor to 34-year-old Fernandinho. City will not be signing Sporting Lisbon's Bruno Fernandes.
With Vincent Kompany's future uncertain, they also want a left-sided central defender.
One player City are certainly keen on is Crystal Palace's 21-year-old right-back Aaron Wan-Bissaka. I'm told they'll face a straight battle with Manchester United and despite preferring to stay in London, he wouldn't be averse to moving north.
City have shown interest in Leicester left-back Ben Chilwell, 22, and Fulham's 18-year-old winger Ryan Sessegnon. But the form of Oleksandr Zinchenko - allied to the problems they would face selling the injury-prone Benjamin Mendy - mean that interest has cooled.
Contract talks were held last summer with Germany midfielder Ilkay Gundogan, however no agreement was reached. And when City approached him again in January, he asked to postpone negotiations until the end of the season. It is understood he is likely to stay, even if he goes into the final year of his contract.
Another player City like is Joe Aribo from Charlton - they've initiated contact in the last 10 days. The 22-year-old left-footed central midfielder has scored 10 goals in 37 appearances and is on their list as a homegrown squad option.
Low-key summer for Liverpool
Jurgen Klopp is a huge fan of 19-year-old striker Rhian Brewster
Liverpool are the most settled of the Premier League's top six and this is a summer of consolidation, having already stockpiled well. They've done their big shop, so don't need to do it weekly.
The feeling is that to improve their squad it would take astronomical spending and there are few 'gettable' players who can come in and be first choice.
Owners Fenway Sports Group (FSG) don't just want to splash out, take a punt or spend for the sake of it; they'd rather be nimble, brave, smart and strategic.
Their aim has always been to get to a stage where they are ready to react and make game-changing signings when the need and the opportunity arise.
They feel they're now at that stage - as shown, for example, post Philippe Coutinho and with the acquisitions of Virgil Van Dijk and Alisson.
Currently the need, opportunity and level of finance required for such game-changing signings is not there.
So unless any unforeseen circumstances arise to change that, it will be a low-key, conservative window at Anfield.
One, maximum two signings - and for fees unlikely to surpass, for instance, the £13m Liverpool spent on Xherdan Shaqiri last summer.
With Alberto Moreno on his way out and Nathaniel Clyne likely to go too, full-back cover - especially on the left - is needed. But not necessarily specialist cover, rather a flexible full-back - somebody who can grow into the role or operate in various positions.
It's a similar situation in attack, with Daniel Sturridge set to depart but unlikely to be replaced like-for-like. Jurgen Klopp is a huge fan of 19-year-old Rhian Brewster and therefore does not plan to recruit a back-up 'number nine'.
Instead, the Reds could sign a versatile attacker, allowing Klopp to shuffle the pack as and when he sees fit. Divock Origi is expected to stay, regardless of whether or not he signs a new deal.
Liverpool don't mind certain players entering the final year of their contracts and ultimately leaving for free, if they see greater relative value in them staying than exiting for a small fee.
Those who have enjoyed successful loan spells away from the club - the likes of Harry Wilson, Ryan Kent and Marko Grujic - could go out again on a temporary or permanent basis. There could also be movement for players such as Ben Woodburn, Sheyi Ojo and Ovie Ejaria.
Liverpool have been linked with Bayer Leverkusen's attacking midfielder Julian Brandt, but it's thought a move for the Germany international will not materialise.
Although they were keen on Brandt in the window before Mohamed Salah was signed, the 23-year-old realised he would not be guaranteed a starting place and decided to stay put. That predicament would be worse for him at Liverpool now and, with that in mind, his £21.5m release clause along with a probable five-year contract and agent fee is not viable.
Similar applies for RB Leipzig's Timo Werner and, previously, the Chelsea-bound Christian Pulisic. Why come to fight for a place when you can be first choice elsewhere?
Liverpool's pursuit of Nabil Fekir a year ago was genuine and at the time he fitted the bill. But in the end Shaqiri was signed, Klopp reworked the shape of his attack and experimented with other players, and he has Alex Oxlade-Chamberlain to return. So as things stand Fekir, Brandt and Werner are not targets.
The unforeseen circumstances mentioned above would include a serious injury occurring or a key player demanding to leave. That said, Liverpool proved with Coutinho they are prepared to give a hard 'no', take the moral high ground and do things on their terms.
Among the players Paris St-Germain boss Thomas Tuchel has eyes on is Roberto Firmino, but it's not something the Reds would even consider.
Transfer ban defines Chelsea's summer
Chelsea could refuse to let Eden Hazard leave this summer, if their transfer ban stands
It all depends on their transfer ban and, because of that, no leading club faces greater recruitment uncertainty. I've heard the Court of Arbitration for Sport may not rule on that case until July, which falls bang in the middle of the transfer window.
Chelsea qualifying for the Champions League has, in one way, given them something of a headache. There are suggestions they may have reluctantly accepted the ban had they been in the Europa League; go with what they've got, get it over and done with.
But now they're in the top-tier competition, Chelsea need reinforcements to help them compete at that level and are, therefore, vigorously fighting the ban.
They desperately want a striker and also a wide attacker.
Should the ban stand, they will almost certainly take up the option of extending striker Olivier Giroud's contract and they can do the same with the on-loan Gonzalo Higuain. Michy Batshuayi and Tammy Abraham are on their books, too, of course.
As for the wide attacker/playmaker, Eden Hazard is being heavily linked with Real Madrid and he wants the switch to happen, but it's not a done deal.
If the ban stands, some feel Chelsea will refuse to let him go, accept missing out on a huge transfer fee and losing him for free a year later, in the hope that keeping him pays off on the pitch. With Pedro and Willian into their 30s and Callum Hudson-Odoi facing a long spell out injured, Hazard could be priceless.
If the ban is suspended, the Blues would be expected to sanction Hazard's departure and I've heard a potential replacement is Coutinho.
With Antoine Griezmann joining Barcelona, somebody needs to make way and the most likely candidate is Coutinho. In addition, his agent, Kia Joorabchian, has done a lot of work with Chelsea over the years.
Other possibilities include Wilfried Zaha of Crystal Palace. The 26-year-old wants to leave Selhurst Park this summer, but there is a feeling among suitors that Palace will set too high an asking price.
Let's not forget the pre-ban signing of Christian Pulisic from Borussia Dortmund, which looks a shrewd piece of business.
In the striking department, Edinson Cavani and Marco Asensio are names that have been mentioned to me. PSG are looking to offload Cavani, whose relationship with Neymar is poor, while Asensio could be used by Real Madrid as part of the Hazard deal.
Tottenham to bid for Sessegnon
Tottenham, Manchester United, Paris St-Germain, Juventus, Borussia Dortmund and RB Leipzig are all after Fulham starlet Ryan Sessegnon
It's going to be a summer of significant change at Tottenham, regardless of what happens in the Champions League final.
They're looking at players who haven't quite made it elsewhere - think Lucas Moura when he was out of favour at PSG, Malcom now at Barcelona - and at players who are not the finished article.
Spurs are fond of Ryan Sessegnon and the feeling is mutual. He would have stayed at Fulham if they had stayed up, but now they're resigned to his exit. They can't afford to lose Sessegnon for nothing next summer - if he went abroad they'd only get half a million pounds in compensation and if it was a Premier League club it would go to a tribunal.
Tottenham are yet to make an offer but the sense is that a bid is incoming and it would then be down to the clubs to agree a fee. They envisage Sessegnon initially playing on the left wing before dropping to left-back long term.
There has also been strong interest in Sessegnon from Manchester United, PSG, Juventus, Borussia Dortmund and RB Leipzig. Chelsea, too, but their transfer ban and the West London rivalry rules that out.
The 18-year-old wants his future sorted before the Under-21 European Championships, which start on 16 June, but Tottenham's participation in the Champions League could delay matters.
Meanwhile, there is a very good chance Christian Eriksen will be sold this summer. With the Dane seemingly unwilling to extend his contract, Spurs will want to avoid losing him on a free transfer next year. There is a slight possibility that he could pen a new deal, with a clause inserted that would allow him to join a leading club like Real Madrid or Barcelona if they made an approach.
Previously, Tottenham have pursued Aston Villa's Jack Grealish and Zaha. Grealish is expected to leave Villa if they miss out on promotion from the Championship, while Zaha can be signed at the right price.
Further back in midfield, Spurs would like to move on Victor Wanyama and possibly Eric Dier.
Centre-back Toby Alderweireld has a year left on his contact and a £25m release clause, so if the Belgian is sold he will need to be replaced. Jan Vertonghen is also going into the final year of his current deal.
Tottenham need a back-up striker as well. Given Fernando Llorente's role in their run to the Champions League final, that could yet be him. But the Spaniard is now 34, so clearly they may look elsewhere.
Arsenal look for Ramsey replacement
Aaron Ramsey is to end his 11-year association with the Gunners this summer
It won't be the most spectacular window, but the Gunners do have some very important business to conduct. The key question is the size of their budget.
With Europa League football, we're told it will be as low as around £40m. But with Champions League football, it will be higher. I've been led to believe that could mean up to £100m.
The higher figure would require player sales and also need to cover the salaries of signings. There's also a revenue boost that will come with Adidas taking over as Arsenal's kit supplier.
The low kitty is mainly explained by Arsenal's heavy investment in recent transfer windows, a total commitment to their self-sustaining model and the adherence to financial fair play (FFP) rules.
Despite the continued absence of a technical director, the existing recruitment team have identified targets and conversations are under way. They're looking for experience and youth.
Their priorities are a central defender and box-to-box midfielder.
Jeremy Wilson from The Telegraph mentioned Getafe centre-back Djene Dakonam, who is under contract until 2021 and has a reported value of £13.5m.
The midfielder will replace the outgoing Aaron Ramsey.
Arsenal came close to a deal for PSG midfielder Christopher Nkunku in January, while Adrien Rabiot is another they've pursued in the past - but I've not heard that either are targets this time round.
Another position they would like to fill is a wide forward. In the last window, they tried to sign Inter Milan's Ivan Perisic and were also talking to Yannick Carrasco of Dalian Yifang. I doubt that interest will be reignited.
Other areas in which they will try to add depth are up front - Danny Welbeck is leaving and there is a desire to send Eddie Nketiah on loan - and at full-back.
Decisions will need to be made on whether youngsters such as Reiss Nelson, Emile Smith Rowe, Joe Willock and Bukayo Saka are loaned out or integrated into the first team.
Manchester United want Koulibaly and Sancho
Kalidou Koulibaly featured 47 times for Napoli this season
United are looking at bringing in a mixture of young talent and experienced big names. And the priority areas for them are central defence, full-back, central midfield and the wings.
Their first-choice centre-back is Napoli's Kalidou Koulibaly, however the Senegal international's hefty price is likely to scupper their hopes.
Koulibaly is 27, under contract until 2023 with a reported 150m euro (£130m) buy-out clause in 2021, and his club have no need to sell.
United will strongly rival Manchester City for full-back Wan-Bissaka, while in central midfield Rabiot is among those on their radar - though much will depend on what happens with Paul Pogba.
The big signing they had been hoping to land was Jadon Sancho.
I'm told he was the Red Devils' top attacking target and that they were his preferred option if he was to return to the UK from Borussia Dortmund this summer. A couple of months ago, he was open to the transfer and those involved felt it was nailed on.
But United's terrible end to the season has changed everything. Sancho is reluctant to give up Champions League football and if he is to move he wants to play for a club where stability, progression, development and a chance of winning trophies is guaranteed.
The 19-year-old England forward now harbours severe doubts that United can offer any of those assurances. I'm told 'never say never', but as things stand it is looking highly unlikely.
PSG, Barcelona and Real Madrid want Sancho, too, but there has been no contact from other Premier League clubs. The transfer fee to prise him from Dortmund this summer would be in excess of £100m, though he is not agitating for a move. It's looking 50-50.