He began his football career in the youth teams of his local professional club, Albacete, with whom he earned promotion from the Segunda División to La Liga in 2003.
He grew up in Leganés, in the greater Madrid area, where his father was stationed, and played football as a midfielder or occasional forward for a team in the district of El Carrascal.
[2] He was as good as his word: Pablo made his Segunda División debut in a 1–1 draw away to Terrassa on 31 August 2002, and went on to start 38 of Albacete's 42 matches as they finished the season in third place and were promoted to La Liga.
[7] A few weeks later, sports agent Alejandro Camaño bought half the rights to the player, thus enabling the club to pay the wages and complete the season successfully.
El País' match reporter described the "promising" Pablo as one of Albacete's mainstays, despite inadequate marking by him and defensive partner Gustavo Siviero taking much of the blame for the opening goal as Osasuna won 2–0.
Amid reported interest from a list of clubs including Manchester City, Arsenal, Leeds United, Roma,[11] Internazionale, reportedly willing to pay around €3 million for the player and then loan him back to Albacete for a season,[12] and Deportivo La Coruña, who agreed terms with the club but were unable to agree with Camaño,[13][14] Pablo signed a four-year contract with Atlético Madrid for a fee of €3.5m plus add-ons.
[15] Partnering Colombian international and fellow newcomer Luis Amaranto Perea in central defence, Pablo contributed to Atlético achieving the third best defensive record in the 2004–05 La Liga season; only Barcelona and Real Madrid conceded fewer goals.
He and Perea repeated their efforts of the previous season as Atlético finished in 10th place with the fourth best defensive record,[20] and he partnered Carles Puyol at the 2006 World Cup.
[24] He kept his place, but in November, an injury sustained against Mallorca was diagnosed as a bruised kidney and fractured vertebrae, which kept him out for some weeks,[25] during which time Zé Castro forced his way into consideration as a starter.
[32] An offer from Real Zaragoza of less than €5m was rejected by the club as insufficient, but despite the arrival of Juanito adding to the defensive competition, Pablo said he was happy to see out the remaining year of his contract.
[35] Despite renewed interest from Camacho, then coach of Osasuna,[36] Pablo moved to England, where he signed a three-year deal with West Bromwich Albion, newly returned to the Premier League, to begin on 1 July 2010 when his contract with Atlético expired.
[43] Away to Club Brugge in the same competition, he was knocked unconscious in a clash of heads with Joseph Akpala for which he received lengthy treatment; in the tenth minute of the resultant stoppage time, Chris Wood scored a winning goal for Birmingham.
[47] Further injuries, the return to fitness of Caldwell, and the emergence of young left-back Mitch Hancox, which allowed Paul Robinson to partner Davies in the centre, meant that Pablo played only twice more, and he was released at the end of his contract.
[52] His first call-up to the senior national squad came in October 2004, for World Cup qualifiers against Belgium and Lithuania, as a replacement for Juanito who dropped out of the original selection because of injury.
[56] Pablo replaced Iván Helguera, who had previously been a regular selection, in the squad for Spain's next match, a World Cup qualifier at home to San Marino in February 2005,[57] but did not play.
[58] A few days later, he made his first competitive international appearance in the goalless World Cup qualifier away to Serbia & Montenegro, playing alongside Puyol in the first half and Juanito in the second.
[2] In later years, he used his experience: in 2012, the Birmingham Mail suggested that, in contrast to the "more aggressive and animated" Steven Caldwell, "Pablo tends to be subtle in his positioning and tackling, he likes to read the game rather than go head-to-head in a gladiatorial battle".