The signings of Gareth Bale and Sergio Reguilon could see Tottenham's formation change as Jose Mourinho completes one of the biggest tactical shifts of his long and illustrious managerial career.
Bale's return would be a major coup for Spurs and reignite enthusiasm from supporters but the onus would be on Mourinho to make best use of his undoubted ability. The acquisition of Bale's young Real Madrid team-mate could prove to be a key factor in achieving that.
It will surely bring a change of formation, one hinted at since Mourinho arrived.
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Right from the start of his Spurs reign, Mourinho's idea was to deploy Ben Davies as a defensive left-back sweeping to cover the centre-backs with Serge Aurier free to race forward and provide the width on the right. Building with a back three was his vision.
The subsequent injury to Davies - sustained in his first game in charge - became a theme of press conferences, as well as the subsequent documentary series on Spurs' season. The loss of Harry Kane cost Spurs points, but it was the injury to Davies that jeopardised his plans.
So wedded was Mourinho to this asymmetrical formation that he ended up utilising Japhet Tanganga out of position there rather than playing the more experienced England left-back Danny Rose. That decision even led to Rose's departure on loan to Newcastle last season.
In conversation with Rose, Mourinho cited the greater physicality of Tanganga as a key factor in his decision. It was a clear indication that the qualities he wanted in his left-back were very different from the demands of the position on the opposite flank.
Serge Aurier was encouraged to raid forward on the right and play a very different role. In part, this was because - something openly stated by Mourinho - he does not trust Aurier in defensive situations. This was him accommodating those weaknesses.
Following Davies' return from injury, Spurs enjoyed some success reverting to the original plan and the transfer business prior to the opening weekend of the season appeared to suggest that the vision for this season was to upgrade rather than overhaul this idea.
The signing of Matt Doherty was widely regarded as a straightforward upgrade even though he had been used as a wing-back at Wolves. Aurier's role was so attacking anyway that it could be argued that a natural wing-back on that right side made more sense.
The move for Reguilon is different. He is not a like-for-like upgrade on Davies. His attacking qualities mean that he is more suited to mirroring the role of Doherty on the right than slotting seamlessly into the existing shape. A formation change would appear inevitable.
Switching to a genuine back three makes sense.
It was as an offensive force rather than a defensive full-back that Reguilon caught the eye for Real Madrid before thriving on loan at Sevilla. Mourinho has operated with attacking full-backs before. But this Spurs defence needs too much help for that to be a serious option.
It is more likely that Reguilon would find himself in the sort of positions that Heung-Min Son has often found himself expected to take up in this lopsided Tottenham formation. With little attacking threat coming from Davies, Son has had to come deeper to collect the ball.
Son could be one of the big winners if Mourinho switches to a 3-4-3 formation because the presence of a wide man outside him on the left would free him to push forward into the box and find himself closer to Kane in attack. That would play to his strengths.
The benefits for Dele Alli are less obvious and perhaps that helps to explain why his name has been mentioned as a possible factor in any deal with Real Madrid. The 3-4-3 formation effectively removes his role - one that is so central to the 4-2-3-1 formation.
While it might seem a negative move to withdraw an attacking midfielder to bring in a full-back, the introduction of Reguilon in his natural position would not only push Son into more threatening areas, providing much-needed support for Kane, but it would help others too.
Doherty would be free to play the wing-back role in which he impressed for Wolves without leaving the wide open spaces behind him that Everton were able to exploit on the opening weekend. Toby Alderweireld playing on the right of a three-man defence would avoid that.
It would also suit Eric Dier, on his return to defence, if he were able to play as a sweeper with defensive cover either side of him rather than as a marker. His experience of years in midfield could even enable him to step up and distribute from there if the game demanded it.
The partnership of Pierre-Emile Hojbjerg and Harry Winks looked bereft of creativity against Everton but greater passing options out wide could alleviate those concerns. The presence of a back three behind them could even allow Giovani Lo Celso to be used in a deeper role.
Having wing-backs stretching the play could see Tottenham's formation become more like a front five in possession with Son and Bale, two potent scorers, getting closer to Kane in attack and delivering the sort of numbers needed to take Spurs forward.
That is crucial to unlocking Bale's full potential.
Getting the best from Bale
The Welshman remains a physical specimen but at the age of 31, the days of him powering past opponents with sheer speed are drawing to a close. While he retains the threat of going by markers on the outside, his chief weapon now is cutting inside on that famed left foot.
With Doherty providing the width, Bale could be used as an inside rather than an outside right - putting him more often in that zone from which he found the net no fewer than nine times from outside the penalty box in his most recent season as a Premier League player.
Nobody has come close to those numbers since. That not only serves as a reminder of just how dangerous that Bale can be but it underlines the potential transformation in potency that his arrival could bring. The heavy scoring load on Kane could be shared.
Lucas Moura scored only four goals in 35 Premier League appearances last season at a rate of one every 562 minutes spent on the pitch. It is a paltry return for a player in the offensive line and a key differential between Tottenham and those teams they aspire to catch.
Liverpool have had great success by feeding the ball to Mohamed Salah and Sadio Mane in the channels with their full-backs providing the width. Could Spurs hope for similar returns from Bale and Son if they can set up the system to position them in those same zones?
It requires special full-backs, hard-working midfielders and centre-backs who are world class in one-on-one situations for Liverpool to make that work in a 4-3-3 formation. For Tottenham, it would seem more achievable with that extra man at the back in a 3-4-3.
It is not a formation that is alien to the club's supporters, of course. Mauricio Pochettino switched to a back three during the 2016/17 season after enjoying success with 4-2-3-1.
He used it to give his side an extra man at the back - notably using it against Watford's two-striker system - while encouraging Kyle Walker and Danny Rose to attack as wing-backs.
Many of the Spurs squad remain from those days so the formation would not be new to them - but it would be a major departure for Mourinho from his tried and trusted methods.
He is a coach who has enjoyed so much success over the past two decades that it would be understandable for him to be reluctant to embrace a formation different to the one with which he has won two Champions League finals and no fewer than seven domestic league titles.
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And yet, it now seems the natural step for his Tottenham team to make a similar tactical tweak to the one adopted by Arsenal, of all teams, under Mikel Arteta. "I think Mikel has found a way for them to play and to be stable and to improve," said Mourinho recently.
Tottenham are in search of that same stability and improvement. If the signings of Bale and Reguilon help them to find it with their own switch to 3-4-3 it would be an evolution for the team - and their celebrated coach.