Question: Walter Samuel played with the defender or midfielder who was of what nationality?

full_context: Document 1: Cristian Zaccardo: Cristian Zaccardo, (] , born 21 December 1981) is an Italian footballer who is currently a free agent. He mainly plays as a centre back, although he is also capable of playing as a full-back or in midfield. He began his club career with Italian club Bologna in 2000, and remained with the club until 2004, aside from a loan spell with Spezia. He subsequently moved to Palermo, where he came to prominence during his four seasons at the club. In 2008, he moved to German club VfL Wolfsburg for a season, where he won the 2008–09 Bundesliga title. He returned to Italy the following season, joining Parma, and in 2013 he moved to Milan, before joining Carpi in 2015; he spent the 2016–17 season on loan with Vicenza in Serie B. At international level, he represented the Italy national football team on 17 occasions between 2004 and 2007, scoring a goal; he was a member of the Italian side that won the 2006 FIFA World Cup.
Document 2: Walter Samuel: Walter Adrián Luján Samuel (] ; born Walter Adrián Luján; 23 March 1978) is a retired Argentine professional footballer. Gifted with natural power and good defensive skills, Samuel has been regarded as one of the best centre-backs of his generation, and as one of football's toughest defenders, with former international teammate and Inter captain Javier Zanetti referring to him as the "hardest player" he has played with.
Document 3: Gary Medel: Gary Alexis Medel Soto (] ; born 3 August 1987) is a Chilean professional footballer who plays for Turkish club Beşiktaş as a defensive midfielder. However, he can also play as a defender. Due to his work-rate, physicality, tenacity, tactical intelligence, and his aggressive, hard-tackling style of play, as well as his leadership on the pitch, he is nicknamed the "Pitbull".
Document 4: 2000–01 A.S. Roma season: In 2001, Associazione Sportiva Roma took its third league title (after 1942 and 1983), winning Serie A only a year after rivals Lazio. Important signings were the Argentines Walter Samuel, a defender, and Gabriel Batistuta, a top striker. Fabio Capello's line-up also included Cafu, Vincent Candela, Emerson, Vincenzo Montella and captain Francesco Totti.
Document 5: Walter Matthysse: Walter Dario Matthysse (born August 29, 1978) is an Argentine former professional boxer who competed from 2002 to 2009, and challenged once for the IBF welterweight title in 2007. He is the elder brother of professional boxer Lucas Matthysse.
Document 6: Juan Sebastián Verón: Juan Sebastián Verón (] ; born 9 March 1975) is an Argentine footballer who plays and serves as the chairman for Estudiantes de La Plata, where he had served as Director of Sports. A former midfielder, Verón's career started in Estudiantes, continued in Argentina's Boca Juniors, and included stints in several clubs in the Italian Serie A (where he won the "Scudetto" with Lazio and with Internazionale, and a UEFA Cup with Parma), and England's Manchester United and Chelsea. In 2006, Verón returned to Estudiantes, where he remained until his retirement in 2014, aside from a brief spell with Brandsen. He has announced his short return to first team will occur in Copa Libertadores 2017.
Document 7: Juan Cuadrado: Juan Guillermo Cuadrado Bello (] ; born 26 May 1988) is a Colombian professional footballer who plays as a winger for Italian club Juventus and the Colombia national team. He is known for his direct style of play, including his pace (both on and off the ball) as well as his dribbling skills. He started off in a central role as a defensive midfielder early in his career before being moved into wider positions in which he now plays as a right winger.
Document 8: Daniel Van Buyten: Daniel Van Buyten (] ; born 7 February 1978) is a Belgian former footballer who played as a centre back. Nicknamed "Big Dan", Van Buyten was known for his uncompromising style of play, exploiting both his physical strength and aerial ability.
Document 9: Walter Montoya: Walter Iván Montoya (born 21 July 1993) is an Argentine professional footballer who plays as a central midfielder for Spanish club Sevilla FC.
Document 10: Paolo Maldini: Paolo Cesare Maldini (] ; born 26 June 1968) is an Italian former professional footballer who played as a left back and central defender for A.C. Milan and the Italy national team. He spent all 25 seasons of his career in the Serie A with Milan, before retiring at the age of 41 in 2009. He won 23 trophies with Milan while in the squad: the UEFA Champions League five times, seven Serie A titles, one Coppa Italia, three Supercoppa Italiana titles, four European Super Cups, two Intercontinental Cups and one FIFA Club World Cup.
Document 11: Fabio Cannavaro: Fabio Cannavaro, (] ; born 13 September 1973) is an Italian former professional footballer and current manager of Chinese club Tianjin Quanjian.
Document 12: Walter Silvani: Walter Gustavo Silvani Ríos (born May 11, 1971 in Quilmes, Argentina) is a former Argentine footballer played in clubs of Argentina, Chile, Mexico, Spain, Uruguay and United Arab Emirates. He played as an attacker.
Document 13: Diego Milito: Diego Alberto Milito (born 12 June 1979) is an Argentine former footballer best known for his time with Internazionale Milano, who last played as a striker for Racing Club and also formerly played for the Argentine national team. A prolific and consistent centre-forward, Milito has averaged just over a goal every two appearances over the course of his professional career.
Document 14: Éver Banega: 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.
Document 15: Javier Zanetti: Javier Adelmar Zanetti (] ; born 10 August 1973) is an Argentine former footballer who played as a defender or midfielder.
ground_truth: Argentine