What you need to know:
- Martin Braithwaite, Samuel Umtiti and Memphis Depay are also candidates to depart the Camp Nou, with the latter reportedly a target for Juventus.
- On top of that, efforts have been made to persuade certain players, including Gerard Pique and Sergio Busquets, to accept wage reductions.
Barcelona's attempts to establish themselves once again as a force in La Liga and the Champions League this season have seen the heavily-indebted Catalans gamble with their future to enable a striking summer spending spree.
A year after being forced to let Lionel Messi go as eye-watering reported debts of 1.35 billion euros ($1.39 billion) crippled the club, Barcelona have spent 153 million euros on transfer fees alone to strengthen their squad, with Robert Lewandowski the most notable new arrival.
"This is a really exciting season. Nothing would give me more pleasure than to make all the fans happy," coach Xavi Hernandez said before last weekend's 6-0 friendly win over Mexican side Pumas UNAM.
"That means winning trophies. That is our main objective."
After three years of struggles, on and off the field, the summer has seen hope return to the Camp Nou, with president Joan Laporta talking of an exciting "new era" when the club unveiled Lewandowski as a Barcelona player.
"Euphoria" was the headline on the cover of local daily Sport the same day.
Even partisan Madrid-based sports daily Marca admitted that Barca were "frightening" in the wake of their drubbing of Pumas UNAM last weekend, when Lewandowski scored his first goal since his arrival from Bayern Munich.
Yet how Barcelona have gone about raising the funds to sign Lewandowski, as well as centre-backs Jules Kounde and Andreas Christensen, AC Milan midfielder Franck Kessie, and Leeds United's Brazilian winger Raphinha has raised eyebrows.
Faced with severe limits on spending in order to comply with La Liga's financial controls, Barcelona knew they needed to raise money quickly to be able to invest in any signings and, crucially, to register any new players.
They quickly set about selling off assets to bring in money by activating a series of what have been called economic "levers".
The club sold 25 percent of their domestic television rights for the next quarter of a century to US investment firm Sixth Street for some 400 million euros.
Barcelona sold 24.5 percent of Barca Studios, which manages the club's digital business and audiovisual productions, to Socios.com for 100 million euros on August 1, and then another 25 percent to US investment firm GDA Luma for 100 million euros more.
In the space of a few weeks, 600 million euros had been brought in to fill the coffers.
The aim was to clean up the club's finances, make it possible to increase the salary limit set by La Liga and allow the new signings to all be registered for the start of the season.
On top of that, Barca signed the biggest sponsorship deal in their history with Spotify, bringing in a reported 435 million euros for the music streaming giant to feature on the club's shirts and to have naming rights to the Camp Nou.
And so Barcelona look well placed to become serious title contenders again as they prepare to host Rayo Vallecano this weekend.
Only time will tell if mortgaging part of the club's assets in exchange for an immediate influx of cash will bear fruit.
De Jong to leave?
Yet, Barcelona are still waiting for La Liga to allow them to register their new signings, although they hope to be able to do so in time for the season.
They are also hoping to further ease their financial problems by reducing their wage bill.
The Catalans have been trying to persuade Frenkie de Jong to leave, with suggestions even made that a contract he signed in 2020 was not legal. The Dutch midfielder says he wants to stay.
Martin Braithwaite, Samuel Umtiti and Memphis Depay are also candidates to depart the Camp Nou, with the latter reportedly a target for Juventus.
On top of that, efforts have been made to persuade certain players, including Gerard Pique and Sergio Busquets, to accept wage reductions.
Barca's "economic miracle", as the press have called it, still has to be transformed into a footballing miracle.