Question: Which Argentine professional footballer who plays as a defensive midfielder or centre-back for Spanish club FC Barcelona and the Argentina national team was contracted under Alberto Dualib?
Context: Samuel Yves Umtiti (] ; born 14 November 1993) is a French professional footballer who plays as a centre-back for Spanish club FC Barcelona and the France national team. Alberto Dualib (born 1920 in São Paulo, Brazil) is a Brazilian businessman of Lebanese descent.  Alberto Dualib was Sport Club Corinthians Paulista's chairman between 1993-2007.  He worked with: Nesi Curi, Clodomil Antonio Orsi, Wilson Bento, Aurélio de Paula, Osmar Stábile, Antonio Jorge, Rachid Junior, Emerson Piovezan, Farid Zablith Filho, Jorge Agle Kalil, Francisco Teocharis Papaiordanou Jr., Ílton José da Costa, Paulino Tritapepe Neto.  He, as the club chairman, made a contract with Media Sports Investments, controlled by Kia Joorabchian, and with the russian oligarch Boris Berezovsky as one of its investors. Renato Duprat is his right-arm. With MSI's aid, Dualib contracted many stars for Corinthians, like: Carlos Tevez, Nilmar Honorato da Silva, Javier Mascherano, Marcelo Mattos, Roger, Gustavo Nery, Carlos Alberto and others. Éver Maximiliano David Banega (] ; born 29 June 1988) is an Argentine professional footballer who plays for Spanish club Sevilla FC and the Argentina national team as a central midfielder. Javier Alejandro Mascherano (] , ] ; born 8 June 1984) is an Argentine professional footballer who plays as a defensive midfielder or centre-back for Spanish club FC Barcelona and the Argentina national team. André Filipe Tavares Gomes (] ; born 30 July 1993) is a Portuguese professional footballer who plays as a central midfielder for Spanish club FC Barcelona and the Portugal national team. Arda Turan (born 30 January 1987) is a Turkish professional footballer who plays as an attacking midfielder for Spanish club FC Barcelona and the Turkey national team. Luis Alberto Suárez Díaz (] ; born 24 January 1987), commonly known as Luis Suárez, is a Uruguayan professional footballer who plays as a striker for Spanish club FC Barcelona and the Uruguay national team.  Widely regarded as one of the best players in the world, Suárez has won 14 trophies in his career, including four league titles, a UEFA Champions League title and a Copa América.  A prolific goalscorer, Suárez has won two European Golden Shoes, Ronaldo de Assis Moreira (born 21 March 1980), commonly known as Ronaldinho (] ) or Ronaldinho Gaúcho, is a Brazilian professional footballer and ambassador for Spanish club FC Barcelona.  He played mostly as an attacking midfielder, but was also deployed as a forward or a winger.  He played the bulk of his career at European clubs Paris Saint-Germain, Barcelona and Milan as well as playing for the Brazilian national team.  Often considered one of the best players of his generation and regarded by many as one of the greatest of all time, Ronaldinho won two FIFA World Player of the Year awards and a Ballon d'Or.  He was renowned for his technical skills and creativity; due to his agility, pace and Thomas Vermaelen (] ; born 14 November 1985) is a Belgian professional footballer who plays as a centre-back for Spanish club FC Barcelona and the Belgium national team. Lionel Andrés "Leo" Messi (] ; born 24 June 1987) is an Argentine professional footballer who plays as a forward for Spanish club Barcelona and the Argentina national team.  Often considered the best player in the world and regarded by many as the greatest of all time, Messi is the only player in history to win five FIFA Ballon d'Or awards, four of which he won consecutively, and a record-tying four European Golden Shoes.  He has won 29 trophies with Barcelona, including eight La Liga titles, four UEFA Champions League titles, and five Copas del Rey.  Both a prolific goalscorer and a creative playmaker, Messi holds the records for most official goals scored in La Liga (358), a La Liga season (50) and a club football season in Europe (73), a calendar year (91), as well as those for most assists made in La Liga (138) and the Copa América (11).  He has scored over 600 senior career goals for club and country.
Answer: Javier Mascherano