Barcelona may not have been as lavish as they were a few years ago when they signed stars like Dembele and Coutinho for hundreds of millions of euros. However, the Catalan giants still have a huge appeal to the best players in the world because of their incredible location and the club's enticing history and prestige. As a result, Barca will reportedly not spend a large sum of money on this summer's transfer window, but will rebuild the team with a few carefully selected players whose contracts expire this summer.
Pogba
You'd be hard-pressed to find a Manchester United fan who still has hopes for Paul Pogba to stay at the club next season, while the France international seems destined for a move to Spain. Although Real Madrid are also linked to the player, Pogba has a close connection with the transfer to Barca, and as the ball organizer at the heart of Xavi's midfield, he will undoubtedly get more opportunities to show his talents at Barca.
Frank Casey
Another player who can offer B-to-B ability in midfield is AC Milan's Casey. Like Pogba, Casey's contract will expire at the end of the season, and if Barca can lure him to ignore the offer from England, they may find that the Serie A striker will be a long-term replacement for Busquets' midfield position for very little.
Christensen
Moving away from the centre of the pitch, Barca will prioritise signing Chelsea defender Christensen to bolster their flawed defence. The Danish international has been linked to Bayern Munich and Borussia Dortmund, but the latest reports from Spain show that the player is now 99% sure to choose to move to Camp Nou in the summer.
Ginter
Another centre-back with close ties to Barca is Germany international Matthias Günter. The tall defender has struggled a bit at Borussia Möncheng this season and he is no doubt looking forward to an early end to the season so he can shake off the shadow of Germany and start over in Spain.
Azpilicueta
Barca look set to strike Chelsea in a double whammy this summer, taking not only Christensen away but also right-back Azpilicueta. While uncertain at the moment, the Spaniard has reportedly received a long-term contract from Barca and he may agree to leave Chelsea, which is being gradually marginalized, and throw himself into Barca's arms.