Born in Seville, Andalusia, and a product of hometown club Sevilla's youth system, Gallardo made his first-team debut aged 20, being instrumental in their 2001 return to La Liga[1] and proceeding to have a further two solid seasons with the main squad.
In November of that year, he was fined and suspended by the Royal Spanish Football Federation for violating standards of "sporting dignity and decorum" after he congratulated teammate José Antonio Reyes, who had just scored, by bending down and biting on his penis.
In the following season he was ousted from the squad alongside José María Movilla by manager Javier Clemente, and spent several months without a team, being reinstated in March 2009 after the coach's dismissal; he was finally released in June.
[12] Gallardo returned to the Ramón Sánchez Pizjuán Stadium in the summer of 2015, first being in charge of the academy and later being appointed at the helm of the amateur team in the Tercera División, with Carlos Marchena as his assistant.
[14][15] In November 2022, Gallardo joined Premier League side Leeds United as first-team coach in Jesse Marsch's staff.