#2 Clement Lenglet
One of the most sought-after defenders in the summer, Barcelona shelled out €36m for Lenglet from Sevilla. He was signed mainly as a backup to Gerard Pique and Samuel Umtiti but with Umtiti suffering from knee problems consistently throughout the season, Lenglet has had a lot more action than he, and probably the club, bargained for.
Lenglet has been a revelation since his arrival. Great in the air and on the ball, Umtiti may have to work his way to displace his French compatriot on present form. Lenglet may lack the physical presence of Umtiti, but he has hardly put a foot wrong in his absence.
If genuine competition for places is what Valverde desires for each position, then he certainly has one at the heart of the defence. Definitely a contender for the bargain of the season. Some may debate that he deserves to be ranked one in this list, but a certain Brazilian has set the Catalan club alight with his performances so far.
#1 Arthur Melo
Xavi 2.0. A signing Barcelona have been crying out for years. Arthur joined Barcelona from Brazilian club Gremio and has been quietly enhancing his reputation. His integration at the club has been steady and was limited to substitute appearances at first but after making his first start against Tottenham Hotspur at Wembley, he has been indispensable.
Protects the ball well, passes it wisely, sets the play up, he is an organiser of play. Arthur has the Barcelona DNA and was born to play for the Catalans. At 22 years of age, things can only go uphill from here. With Barcelona already announcing the signing of Ajax midfielder Frenkie De Jong for the next season, we could be seeing the next Xavi Hernandez and Andres Iniesta.