Barcelona are said to be closely monitoring the future of RB Leipzig starlet Dayout Upamecano and Ajax youngster Matthijs de Ligt ahead of making a future move to lure one of them to the Nou Camp.

Mundo Deportivo reports that Ernesto Valverde's side are ready to step up the scouting of the two defenders after having identified the signing of a centre-back as their next transfer priority.

The La Liga giants made four additions to Valverde's squad during the summer transfer window in the form of Paulinho, Nelson Semedo, Gerard Deulofeu, Ousmane Dembele.

Furthermore, the club also activated an option to sign Brazilian centre-back Marlon Santos on a permanent basis before sending him on loan to Nice on a two season-long deal in order to continue his development.

However, it looks like the recruitment of Marlon is now enough for Valverde with Mundo Deportivo saying that the Spanish boss wants to bolster the position further in the coming transfer windows.

Gerard Pique and Samuel Umtiti have formed a solid partnership in the start of the new season but Javier Mascherano is already 33 years old while fourth choice centre-back Thomas Vermaelen is yet to play a single minute since he returned from a disappointing loan spell at Roma.

Barcelona have an option sign 22-year-old Colombian centre-back Yerry Mina from Palmeiras which they are expected to trigger either in January or next summer.

Mundo Deportivo says that Valverde has earmarked the signing of another centre-back as a priority after a the summer in which Barcelona failed to complete the signing of Iñigo Martinez from Real Sociedad.

The Spanish publication says that Barcelona scouts are closely tracking two 18-year-old prospects in Upamecano and Matthijs de Ligt.

Barcelona were already linked with the former last year before he opted to complete a move from Red Bull Salzburg to RB Leipzig in January. Meanwhile, the Ajax defender impressed the Catalans' scouts last year while forming an impressive partnership with new Tottenham signing Davinson Sanchez.

Nice's Malang Sarr, Bayern Munich's NIklas Sule, Bayer Leverkusen's Jonathan Tah and AC Milan's Alessio Romagnoli are also mentioned as potential young alternatives while Barcelona have not ruled out the possibility of breaking the bank to sign a more experienced defender.

Mundo Deportivo add that the club are still keen on signing a top class defender in the mold of Martinez, Aymeric Laporte, Emanuel Mammana or Southampton's Virgil van Dijk.