Question: Which club was involved in the race for La Liga title for the first time in many years in the 2002-03 season?

Context paragraphs:
2002–03 Real Sociedad season: In the 2002-2003 season Real Sociedad were involved in a title race for the first time in decades.

2004–05 FC Barcelona season: The 2004-05 season saw Fútbol Club Barcelona end their six-year wait for the La Liga title, having not won the league or, indeed, any trophy since the 1998–99 season and thus La Liga trophy returned in Barcelona's trophy room.  Having finished second in La Liga the previous season, Barcelona once again competed in the UEFA Champions League as well as the Copa del Rey.  The squad was restructured significantly following the retirement of key players Luis Enrique and Marc Overmars, as well as the return of Edgar Davids to Juventus and first team regulars Patrick Kluivert and Phillip Cocu moving onto new clubs.  Ronaldinho's and new signing Samuel Eto'o's performances won them places in FIFPro's XI of 2004–05.  Ronaldinho was later named FIFA World Player of the Year for 2005 for the second time in succession and with the highest points total ever; Eto'o came third.  This season was also notable for the debut of Lionel Messi.

2009–10 La Liga: The 2009–10 La Liga season (known as the "Liga BBVA" for sponsorship reasons) was the 79th La Liga since its establishment.  Barcelona were the defending champions, having won their 19th La Liga title in the previous season.  The campaign began on 29 August 2009 ended on 16 May 2010 due to all top-flight European leagues ending earlier than the previous season because of 2010 FIFA World Cup.

2005–06 FC Barcelona season: The 2005–06 season was Futbol Club Barcelona's 107th season in existence and 77th consecutive season in the top flight of Spanish football, La Liga.  It was manager Frank Rijkaard's third season in charge of the club, a season in which he managed to successfully retain the La Liga title, as well as winning the UEFA Champions League and Spanish Super Cup.  The squad was largely unchanged from the previous season, with only two players – Santiago Ezquerro and Mark van Bommel – joining the club.  Gerard left on a free transfer during the summer.

2002–03 La Liga: The 2002–03 La Liga season, the 72nd since its establishment, started on 31 August 2002 and finished on 22 June 2003.

Real Sociedad: Real Sociedad de Fútbol, S.A.D., more commonly referred to as Real Sociedad (] ; "Royal Society") or La Real, is a Spanish football club based in the city of San Sebastián, Basque Country, founded on 7 September 1909.  It plays its home matches at the 32,000-capacity Anoeta Stadium.  Real Sociedad won the Liga title in 1980–81 and 1981–82, and last finished runners-up in 2002–03.  The club has also won the Copa del Rey twice, in 1909 and 1987.  It contests the Basque derby against rivals Athletic Bilbao.  Real Sociedad were founder members of La Liga in 1928, and its longest spell in the top flight was for 40 seasons, from 1967 to 2007.

Lionel Messi: 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.

2002–03 Celta de Vigo season: Celta de Vigo participated in La Liga, Copa del Rey and the UEFA Cup in the 2002-03 season, for the first time qualifying for the UEFA Champions League, thanks to a fourth-placed finish in La Liga.  This was the crown of the work former coach Víctor Fernández had put in to establish Celta as a credible force, and it was under Miguel Ángel Lotina's leadership the club reached the ultimate level of the "Euro Celta" era.

2007–08 La Liga: The 2007–08 La Liga season, the 77th since its establishment, started on 25 August 2007 and finished on 18 May 2008.  Real Madrid defended their La Liga title successfully after a 2–1 victory over Osasuna.  This season, all European leagues ended earlier than the previous season, due to the UEFA Euro 2008 championship.  It also was the first year of the new La Liga television agreement that had La Sexta mark its first year of television broadcasting.

2002–03 Real Madrid C.F. season: The 2002–03 season was Real Madrid's 72nd season in La Liga.  This article shows statistics of the club's players in the season, and also lists all matches that the club played in the 2002–03 season.

Supporting paragraphs: 2002–03 Real Sociedad season 2002–03 La Liga
Answer: Real Sociedad