Born in Barcelona, Catalonia, Serrán was a product of RCD Espanyol's youth system. He appeared in three La Liga games with the team, his debut coming on 11 March 2007 in a 1–1 away draw against Racing de Santander; during his tenure at the Estadi Cornellà-El Prat, however, he was mainly registered with the B-side. Deemed surplus to requirements following Tintín Márquez's appointment to the managerial post at the Estadi Olímpic Lluís Companys, Serrán signed a three-year contract with Swansea City in the Football League Championship, with teammate Jordi Gómez also making the move on a loan deal. The link contained a buy-back clause that allowed Espanyol to re-sign the player at a later date, but it was later revealed that such clause did not exist; however, the Pericos retained the first option should the Welsh club wish to sell in future. Serrán was released by Swansea at the end of the 2010–11 season, which ended in Premier League promotion. He joined AEK Larnaca FCin Cyprus shortly after, having already reached an agreement with the team in May. After five years abroad, Serrán returned to Spain and signed for AD Alcorcón in Segunda División. Subsequently, he moved back to the Cypriot First Division, first with Anorthosis Famagusta FC then former club AEK. On 17 June 2017, Serrán began negotiations with Albanian Superliga champions FK Kukësi. He was presented three days later as a replacement for Albi Alla, penning a one-year deal with an option of a further one worth €60,000 which made him one of the highest-paid players in Albanian football history. His contract also included a clause in which the club would find a school for his six-year-old daughter, and he spoke of the "dream of playing in the UEFA Champions League" during his presentation; on 20 July, however, he was released by mutual consent alleging personal problems. In September 2017, 33-year-old Serrán signed with Moroccan club Chabab Rif Al Hoceima. On 31 August of the following year, he joined Indian Super League's Bengaluru FC on a one-year contract.
