£450m spent, 11 new arrivals, but what is Chelsea's best starting XI after the Blues' disappointing start to the new season?

Pochettino's first port of call may well be his formation; Chelsea have set up in a defensive-looking 3-4-2-1 shape so far this season, with Conor Gallagher, Enzo Fernandez and Moises Caicedo - none of whom are known for their attacking output - crowding the midfield.

The arrival of Cole Palmer from Manchester City should facilitate a return to tactician's preferred fluid 4-2-3-1 shape, with the 20-year-old potentially slotting into the No.10 role that was surely intended for injured blockbuster arrival, Christopher Nkunku.

Pochettino needs to find a way to get the best out of the forward players, and a more attack-minded set-up should be the first step towards doing just that.

This is one area of the pitch where Chelsea have little choice; would-be first-choice goalkeeper Kepa Arrizabalaga was strangely allowed to depart the club on loan to join Real Madrid, with Edouard Mendy having been sold to Saudi side Al-Ahli earlier in the summer.

That leaves £25 million summer signing Robert Sanchez as the main man between the sticks, the Spaniard having ranked 19th out of Premier League goalkeepers in shot-stopping last season, with a post-shot xG minus goals allowed (the most reliable metric for measuring shot-stopping ability) of -2.8.

The decision to not go after a new No.1 could backfire horribly.

Reece James is close to a return from his latest injury setback. Although he isn't usually best suited to a flat back four, with his extraordinary attacking capabilities diminished somewhat, Pochettino's more fluid system should suit him well.

The Argentine demands that his full-backs bomb forward at every opportunity to provide support to the attack, and James is a player who will need no second invitation to do so.

Indeed, despite being nominally a defender, he is one of Chelsea's most important attacking outlets when fit and in form. He needs to steer clear of further injury, though, with summer arrival Malo Gusto already showing he can be an able deputy with two assists in four games.

Thiago Silva's early-season performances have been called into question by some sections of the Blues' support, but he remains the club's most reliable centre-back as he approaches his 39th birthday.

Chelsea have positioned themselves so that they have plenty of options when the Brazilian does move on, with younger defenders Levi Colwill, Wesley Fofana, Benoit Badiashile and Axel Disasi all highly-regarded.

However, for the time being there is no substitute for the veteran's quality and experience, and he can impart his wisdom on whomever his centre-back partner might be. It's a situation his manager will have to monitor, though, and if his powers are on the wane the time may come for him to be gradually phased out of the starting line-up.

The latest poster boy of the Chelsea academy, Colwill needs to be playing if he is going to reach his lofty potential. He has made a steady start to life back at the club, although he has been caught out on a couple of occasions as he covers for the left-back in Pochettino's flexible shape.

However, a switch to a back four could get the best out of him, and with Badiashile sill making his way back from injury and Fofana out long-term, he represents the best option to partner Silva.

The gaffer certainly believes in him, recently saying he believes he can become one of the best centre-backs in the country.

Just like James, Pochettino's preference for attacking full-backs should suit Ben Chilwell down to a tee, continuing to play as a de facto wing-back while a defensive midfielder drops deep to cover in his absence.

The newly-appointed vice-captain has already picked up one assist and has spent much of his time camped in opposition territory so far this term. It seems ridiculous to say, but he does need to improve his end product and finishing, and - like James - he will be desperate to avoid another injury-hit season.

With a solid run in the team and under Pochettino's watchful eye he can become one of Chelsea's most potent attacking weapons once again.

The £115 million ($143m) man, Moises Caicedo, has endured a far from ideal start to life at Chelsea, making two errors leading to goals in just three Premier League appearances as he conceded a penalty at West Ham and stumbled to give the ball away against Nottingham Forest in the lead-up to their winner.

Caicedo has visibly lacked match sharpness, which is little surprise given he had very little involvement in Brighton's pre-season schedule amid an intense transfer tussle between the Seagulls, Chelsea and Liverpool.

Theoretically, playing the full 90 minutes for Ecuador in two World Cup qualifying games on the other side of the globe should help his match fitness, but it remains to be seen what shape he will return in. Despite his poor start, Pochettino will lean on him heavily as the defensive-midfield anchor of the team.

It speaks volumes that chatter about Enzo Fernandez's exorbitant January price tag has become muted since the new season began. The Argentine has been in supreme form under his compatriot so far, looking every bit the midfield linchpin that the Chelsea ownership wanted to build their team around.

He is thriving in a more advanced box-to-box role, linking the midfield and attack, with credit due to his manager. "He is a No.8," Pochettino told Sky Sports. "One of the first things when we met him is to talk about his position and how he feels comfortable, and then to talk about his quality. He needs some freedoms. He has the quality to assist, to shoot from outside the box."

The first name on the team sheet, Chelsea will need this form to continue if they are to kick on after the international pause.

Noni Madueke has been eased back into life at Chelsea after a busy and successful summer with the England Under-21s at the European Championship, but now could be the time to unleash him.

The winger has been on an upward trajectory since emerging as a key attacking player in the latter stages of last season, regularly tormenting defenders with his footwork and dribbling ability, but he is yet to start a Premier League game in 2023-24.

However, a dazzling display in the Carabao Cup, albeit against Wimbledon, reflects that he is still brimming with confidence. Carney Chukwuemeka's injury has opened a space in the wide areas and Madueke seems primed to take it.

Even in just under half-an-hour on the pitch on his debut against Forest, Cole Palmer demonstrated that he is ready to be thrown in at the deep end. Indeed, he could be the perfect solution for the attacking midfield role.

Signed seemingly as mitigation for the serious knee injury to Christopher Nkunku as Chelsea went in search of a player capable of operating as a No.10 or a winger, the £42.5m ($53m) signing from Man City floated about menacingly between the lines, always looking to create and probe.

Given the players at his disposal, the England U21 international may be Pochettino's only option for the attacking midfield role if he wants to shift to his favoured 4-2-3-1.

Raheem Sterling divides opinion among the Chelsea fanbase, but there is no doubt that he has been the club's best attacking player in 2023-24 to date with two goals in four games and a number of scintillating displays.

Pochettino has gotten the best out of him as an inverted winger on the right-hand side, but a tweak in shape and personnel could see him shifted back over to his customary left-wing role.

However, he may still operate more centrally having outlined his preferred position to Pochettino. "Our first conversation with all of the players, and Raheem, I love to ask the position they love to play, how they feel, how they see themselves," the coach said recently. "It's not the position, it's the animation and the way the team is going to link in between them. It's to find the best position...to provide the best platform, position and place and link with the player where they can (show) their best quality."

The jury is out on whether Nicolas Jackson can become a reliable goalscorer in the Premier League, but Chelsea have little option but to persevere with him for the time being.

So far, he has demonstrated that he has almost all of the attributes required to be effective except a finishing touch, as noted by his manager, with his glaring miss in the dire defeat to Nottingham Forest emblematic of that.

Asked whether he believed Jackson could become prolific, Pochettino said recently: “Yes, of course. but he needs time. He needs to adapt to the Premier League. Sometimes he is a little bit rushed in his decisions, but this is only to say he needs to settle himself, be more calm and more relaxed and for sure he is going to score goals."

A semi-favourable fixture list before the next international break provides the 22-year-old with a chance to prove his worth. If he fails, then the returning Armando Broja will be waiting in the wings.