Barcelona's season could hardly have gone better so far; despite a summer of unrest, the Catalan club are top of La Liga, cruising in the UEFA Champions League and unbeaten in 2017/18 under new manager Ernesto Valverde since the Supercopa loss to Real Madrid.

While no manager is likely to be 100 per cent happy with his squad just a few months after taking over, Valverde must be pleased that new signings are integrating nicely—injured Ousmane Dembele aside—and most senior players are adapting to his methods, including those affected by a change of shape.

Still, a January recruitment wouldn't go amiss, and the rumour columns are already full of suggestions, with Mundo Deportivo pressing (in Spanish) Luis Suarez on a possible Philippe Coutinho deal, Marca suggesting Paco Alcacer has put himself in the shop window and Sport (h/t AS) claiming Sevilla's Clement Lenglet is a target.

Coutinho is just one of those whose name is consistently linked with a move to Barcelona. While he might be a good fit for the Camp Nou side or a rapid return for Neymar—unlikely, though jokingly discussed by Valverde—would be immense, the Catalan side should look to another face: Tottenham Hotspur playmaker Christian Eriksen.

Tactical change

From the long-standing 4-3-3 system Barcelona have been famed for, Valverde has this term ushered in a system much more akin to that which he used at Athletic Club. While that was a straightforward 4-2-3-1, this season Barcelona have been using a variation to play four across the midfield and have Lionel Messi central and free in the attack, supporting a single striker—usually Suarez.

The big difference in terms of shape, aside from having Messi in the middle, is that the two interiors are no longer the No. 8s, but instead the two outside members of the quartet are players who drift inside, operating in the channels and even narrower. Playing between the lines leaves the full-backs to do what they've always done: overlap, open up passing lanes and get into advanced positions.

Andres Iniesta has been a regular on the left side of the midfield quartet, with a rotating cast on the right: Denis Suarez, Gerard Deulofeu and most recently Alcacer, with Dembele sidelined.

While the former Dortmund youngster is likely to become a regular starter, consistency and quality might yet be an issue in the short term—while in the mid-to-longer term, Iniesta's advancing age means he plays 90 minutes with less frequency, and Barca could do with someone capable of covering both sides without seeing a drop-off in quality.

This is where Eriksen comes in.

The Danish midfielder has occupied various roles at Tottenham; usually a No. 10, he has also featured from the sides of the attacking line in a 4-2-3-1 and now plays as one of two supporting midfielders behind a lone striker.

His movement and intelligence off the ball ensures he can be effective from any role, seeking out space to receive the ball in, turn and look to play forward.

Barcelona dominate matches still, territorially as well as in possession, so playing from either side of midfield doesn't leave the players in a "wing" position—it's very much an attacking-midfield area of the pitch where Iniesta and Co. have been affecting play this term.

From either side, Eriksen can play his clever link-up passes, is of similar style to Iniesta or Rakitic in terms of quickly releasing possession and having the vision to spot runners ahead of him, and should be a perfect stylistic fit for the Camp Nou side.

Naturally, he's more than capable of playing centrally, too, for those occasions when Valverde switches back to a 4-3-3 or needs a schemer instead of Messi to play in the 10 zone.

Burden of creativity

Barcelona don't lack for talent in their offensive-midfield ranks, even without considering the fact they have Leo Messi at the centre of their game plan.

Aside from Iniesta and Rakitic, there's a handful of players who can create chances when on form—Suarez, Denis, Deulofeu and Rafinha, when fit—but perhaps it's still fair to say that the majority of Barcelona's best buildup play is shared between Sergio Busquets' passing from deep, Iniesta's intuitive play and Messi's all-round genius.

Add Eriksen to the mix and another source of chances is guaranteed.

In fact, it's an area Barcelona need to up their game in; despite all the wins and positive results, they're ranked 16th in Europe's top five leagues for average shots per league game, and seventh for shots on target. While hardly disastrous, there have been games where they've struggled to create high-value chances to score: Atletico Madrid and Olympiakos are the recent games that spring to mind.

Eriksen delivers an excellent set piece, his passing between the lines is effective and, with movement around him, he can open up defences at will.

It should be noted that his shooting is an under-appreciated aspect of his game; while not a 20-goal-a-season midfielder by any stretch, he does consistently contribute—four this term already, 12 last season and eight in 2015/16. In the same campaigns, Rakitic, for example, managed one (so far), eight and nine.

And it's not all about on-the-ball productivity for Eriksen, either.

Earlier in his career, he was regarded as a luxury, an inconsistent star-in-waiting who went missing at times—but his work rate has increased tenfold.

There is no player who covers more ground in Champions League matches than him this season: 140.5 metres per minute on the pitch, according to UEFA's data (h/t AS).

Continuity vs. transition

It isn't a huge problem at the moment for Barcelona, but the squad isn't one that is likely to remain in place for another half-a-dozen years.

Gerard Pique is 30, Busquets and Rakitic 29, Iniesta 33, Messi and Suarez 30. An amount of regeneration will have to occur in the next three or four transfer windows; it has already started with Dembele, but only youth isn't the way to go.

Samuel Umtiti is 23, Marc-Andre ter Stegen is 25, and these are prime-age, elite-level, first-team stars now who can also be Barcelona's future as new players come in. Eriksen, 25, falls in the same category.

Whether Barcelona continue with a four-man midfield or revert to 4-3-3, the Spurs man fits tactically. Stylistically, it's doubtful that Barca will evolve into a counter-attacking or defence-first side, so he also fits the template for player types.

Looking a little further into the future, when Messi finally departs—and with his contract still up in the air, that's a relevant question—there has to be a creative force in place who can replicate his ability to create chances; Eriksen can do that, and from a pure No. 10 role if required, while the club focuses on replacing the goal tally that Messi's departure will leave behind.

In short, Eriksen is a player who can aid the team now and contribute to making it better, but he's also a player who can help usher in the next age at the club—with Messi preferably, but someone who can stand up and be counted even if he's not there.

Real Madrid have already been linked with two of Spurs' stars, with Marca claiming both Dele Alli and Harry Kane are on the titleholders' watch list. But it's the third part of that attacking triumvirate, Eriksen, who best suits Barcelona and who they should be considering as a January reinforcement.

Stats via WhoScored.com.

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