Question: What is the birthday of the Argentine defender Associazione Sportiva Roma signed before the 2001 season?

full_context: Document 1: 1997–98 A.S. Roma season: Associazione Sportiva Roma was reinvigorated under new coach Zdeněk Zeman, who recently had been coaching arch rivals Lazio. Zeman brought his attacking 4–3–3 with him, resulting in Roma scoring 67 goals, but also conceding 42, an extreme rarity in defensive-minded Italian football. Roma finished fourth, three places above Lazio in the table. That was the first time it had happened in five years, which delighted the Roma board, and Zeman stayed on for a further season. The season also saw the international breakthrough of former youth-team product Francesco Totti, who at 21 was ready for increased responsibility and captaincy, responding with 13 league goals from a position on the left-wing of the attack. Also noticeable was new signing Cafu's offensive skills as a right-wing back, granting him a reputation among the world's top wing backs.
Document 2: 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 3: 2002–03 Parma A.C. season: Parma Associazione Calcio regained its respect following a lacklustre Serie A and Champions League performance the year before. Under new coach Cesare Prandelli, Parma played an offensive 4–3–3 formation, in which new offensive signings Adrian Mutu and Adriano starred. Both made up for the departure of Marco Di Vaio to Juventus. Mutu scored 18 goals from the left wing, and Parma accepted a multimillion-pound offer from Chelsea in the summer, which meant the Romanian international only spent a year at the club. Also impressing were goalkeeper Sébastien Frey and young centre-halves Matteo Ferrari and Daniele Bonera, who proved to be acceptable replacements for departed captain Fabio Cannavaro, who had joined Inter in late August 2002.
Document 4: 1985–86 A.S. Roma season: Associazione Sportiva Roma had a successful season, in which Sven-Göran Eriksson's typical Scandinavian tactical approach was able to improve Roma's fortunes to a level where they once again fought for the league title. They also won the Coppa Italia, but the chance of a double disappeared in a 3–2 loss at home to bottom side Lecce, which all but secured Juventus's title. The most important part in Roma's revival was an efficient midfield with several top-class players in addition to striker Roberto Pruzzo, with several playmakers providing multiple assists to league topscorer Pruzzo.
Document 5: 2002–03 A.S. Roma season: Associazione Sportiva Roma crashed down to earth following its previous two remarkable seasons, where it had won Serie A in 2000–01 and finished a close second in 2001–02. Despite the acquisition of Pep Guardiola as central midfielder, he did not apparently fit into Fabio Capello's first-team plans. The squad was essentially the same as the year before, and Guardiola's absence from the starting XI spoke volumes about the reputation of the Roma players at the time. However, things began to go against Roma following its tense competition in Serie A with Juventus. Suspecting things were amiss, both chairman Franco Sensi and manager Capello publicly condemned the judgements, and given the Calciopoli scandal in 2006, chances are they had a point.
Document 6: 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 7: 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 8: 1989–90 A.S. Roma season: Associazione Sportiva Roma had a rather average season, but finished solidly inside the top half of Serie A with a sixth place. German striker Rudi Völler had his best season at Roma, scoring 14 league goals, whilst Stefano Desideri hit 10 goals. The greatest success of Roma's season was the Primavera team winning the national championship.
Document 9: 1994–95 A.S. Roma season: Associazione Sportiva Roma was rejuvenated in Carlo Mazzone's second season as coach, much due to Abel Balbo being the goalscorer it had lacked for the previous years. The summer signings of 1994 helped, with internationally recognized players Jonas Thern and Daniel Fonseca joining the club from rivals Napoli. Also Francesco Moriero became a household player since he proved his worth in the club, recently coming from Cagliari.
Document 10: 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 11: 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 12: 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 13: Javier Zanetti: Javier Adelmar Zanetti (] ; born 10 August 1973) is an Argentine former footballer who played as a defender or midfielder.
Document 14: 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 15: 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.
ground_truth: 23 March 1978