Three things we learned as Chelsea beat Brighton in seven-goal thriller

Chelsea's new-look project under Xabi Alonso is beginning to take shape after the Blues secured a thrilling 4-3 victory over Brighton at Stamford Bridge.

It was far from comfortable, but Chelsea's attacking quality ultimately proved decisive as Cole Palmer, Morgan Rogers and Joao Pedro caused Brighton major problems.

The result maintains Chelsea's perfect Premier League start and gives Alonso three victories in the space of a week, despite significant questions surrounding Enzo Fernandez and Robert Sanchez ahead of Tuesday's transfer deadline.

Here are three key takeaways from Chelsea's victory.

Emiliano Martinez was thrown straight into Alonso's starting XI just hours after Chelsea confirmed his £7.5million transfer from Aston Villa.

The Argentine immediately replaced Sanchez, whose omission from the squad further underlined Chelsea's change of direction in goal.

Conceding three times is hardly an ideal debut statistically, but Martinez could do little about Brighton's goals. More importantly, he provided the calmness and authority Chelsea have often lacked at the back.

There were periods when Alonso's defence looked considerably more secure, although individual errors remain a concern.

Eliminate those lapses and Chelsea may finally have the experienced goalkeeper required to stabilise their defensive unit.

For the second consecutive match, Fernandez was completely absent as speculation surrounding a potential transfer continues.

Alonso instead made the unusual decision to use Malo Gusto alongside Romeo Lavia in midfield, with Lavia producing an energetic performance that strengthened his case for more regular football.

Moises Caicedo was initially overlooked, while Reece James was later introduced centrally as Alonso sought greater leadership when Brighton increased the pressure.

Valentin Barco also received minutes following his arrival from Strasbourg.

The number of combinations being tested suggests Alonso has not yet settled on his preferred midfield partnership.

Much could depend on Fernandez's future. With the midfielder heavily linked with Manchester City, Chelsea may yet enter the market again, with Lamine Camara and Alex Scott among the potential options.

That decision could define the final days of Chelsea's window.

Chelsea's biggest reason for optimism is their attack.

Palmer, Rogers and Joao Pedro already look remarkably comfortable together despite having played in Alonso's new system for only a matter of weeks.

Palmer and Rogers have been given significant creative freedom behind the striker. Rogers' athleticism and ball-carrying repeatedly stretched Brighton, while Palmer found pockets of space before becoming increasingly influential late in the contest.

Joao Pedro provided the focal point.

Wearing the No.9 shirt, the Brazilian combined physical centre-forward play with intelligent movement, dropping deep to connect attacks while also causing Lewis Dunk and Luka Vuskovic problems with his movement.

Questions have previously surrounded whether Joao Pedro can consistently lead the line, but this performance offered an emphatic answer.

Chelsea still have issues to resolve, particularly defensively and in midfield, but Alonso already appears to have found an attacking combination capable of deciding matches.

Chelsea's immediate attention turns towards Tuesday's transfer deadline and resolving the Fernandez situation. His future could determine whether Alonso receives another midfielder before the window closes.

On the pitch, the signs are increasingly encouraging. Chelsea still need to eliminate the defensive mistakes that allowed Brighton back into the contest, but their new attacking structure already looks capable of causing serious problems this season.