Santiago 'Santi' Castillejo Castillejo (born 5 September 1971) is a Spanish retired footballer who played as a striker, and is the current manager of FC Ascó.
He was the all-time scoring leader in Segunda División B, with 184 goals in representation of seven clubs. His La Liga input consisted of 11 games, with Osasuna.
After retiring in 2008, Castillejo worked as a manager.
Born in Valtierra, Castillejo started his football career with local CA Osasuna, being mainly associated with the B-team and scoring 20 Segunda División B goals with the side in the 1992–93 season. He made his La Liga debut with the main squad on 14 March 1993, appearing as a late substitute in a 1–0 home win against Real Zaragoza, and featured in just ten games in his only full campaign, which ended in relegation; he was also loaned to Deportivo Alavés during his spell.
Released by the Navarrese in the 1996 summer, Castillejo resumed his career in Segunda División but also in the third level, with CD Numancia, CD Castellón, Gimnàstic de Tarragona – he netted 21 times as the club achievied promotion to division two in 2001, best in Group III, second overall – UB Conquense, CD Leganés and CF Reus Deportiu, retiring in 2008 at the age of 37.
Immediately after retiring, Castillejo started working as a manager, initially being an assistant with Reus in Tercera División. He was appointed head coach for 2009–10, leading the team to promotion in his second season.
Castillejo agreed on a return to former club Gimnàstic in late May 2013, being appointed for the 2013–14 campaign. On 4 November, he was relieved of his duties.
On 26 June 2014, Castillejo took the reins of UE Llagostera, freshly promoted to the second level. He was sacked on 21 October, after leaving the club in the relegation zone.As of 15 May 2016