Defense
Left-back: Jordi Alba
Jordi Alba will definitely keep his spot in the starting lineup next season. The Spaniard is still in good shape to carry on for the next one or two years. His performances for Spain at the European championship this summer showed that he still has some fuel left in his tank.
Alba's marauding runs and link-up play will be needed by Barcelona to break down opposition defenses. The defender contributes a significant number of goals and assists every season, making him a vital asset for the Catalan giants, especially in the post-Messi era.
Center-back: Gerard Pique
The Spanish centre-back will continue to lead the defensive line next season. He is one of the most experienced players in the squad, exhibiting a laudable character when it comes to influencing the performance of the team.
Pique has shown promising signs in recent friendly games that he has played for Barcelona within the past few weeks. It has been claimed that the defender has maintained a great level in training as well, which would be good news to the ears of the fans.
Center-back: Ronald Araujo
One of the few things we can learn from Barcelona's pre-season outing this summer is that Ronald Araujo is ready for a big role in the team. The defender was one of the standout performers in the Joan Gamper trophy clash with Juventus, putting up a rock-solid display as the Catalan giants secured a 3-0 victory.
Araujo broke into Barca's first team last season. Despite being just 22 years old, the Uruguayan played with a lot of confidence and composure, and was without doubt the best centre-back in the team throughout the campaign.
He made 33 appearances for the club across all competitions, scoring twice and setting up another.
Right-back: Sergino Dest
Making a choice between Sergino Dest and Emerson Royale will certainly be a difficult task for Ronald Koeman as both players were incredible last season. However, Dest will narrowly get the nod because he was part of the team last season, compared to his counterpart who just arrived this summer.
The USA international had a good debut campaign at Camp Nou, making 44 appearances for the Blaugrana across all competitions and recording three goals and one assist to his name. His numbers will surely increase next season.