Sergio León

Elche In the summer of 2013, León joined Elche CF on a four-year deal, being assigned to their reserves and then loaned to Real Murcia CF. After only three competitive appearances for the latter he was recalled by his parent club, continuing to feature and score regularly for the B's.

On 12 July 2014, León was again loaned to a second-tier club, UE Llagostera, for the upcoming season. In the second matchday, he scored his first professional goal to open a 2–0 victory over CD Leganés at home for the team's first professional win. He eventually finished as top scorer for the Province of Girona side, who finished ninth.

León subsequently returned to Elche, and was promoted to the first team which had suffered top-flight relegation for financial reasons. He made his competitive debut for the Valencians on 23 August 2015 by playing the full 90 minutes as they opened their campaign with a 2–0 defeat at SD Ponferradina, and a week later scored his first goal to win a match 2–1 against Bilbao Athletic at the Estadio Martínez Valero. He was the Segunda División Player of the Month in September 2015, having contributed three goals and an assist, and eventually won the Pichichi Trophy for top scorer, netting his 22nd from the penalty spot in the final game against AD Alcorcón to overtake Córdoba CF's Florin Andone.

Osasuna León signed a four-year contract with CA Osasuna on 24 August 2016, for an undisclosed fee. He made his debut in the top division three days later, replacing Oriol Riera in a 2–0 home loss against Real Sociedad. He scored his first goal in the competition on 22 September, to equalise in a 2–1 loss to RCD Espanyol again at the El Sadar Stadium.

On 17 October 2016, León scored a brace in a 3–2 away defeat of SD Eibar. He repeated the feat the next 9 April, in a 2–1 home victory against CD Leganés. He finished the season with a squad-best ten goals, but his team suffered relegation.

Return to Betis On 1 June 2017, León returned to Betis after agreeing to a four-year deal, for a rumoured fee of €3.5 million. He was the club's top scorer with 11 goals as they qualified for the UEFA Europa League in his first season, though he played less frequently in the second half of the campaign following the promotion of Loren into the first team.

Levante León joined Levante UD on a three-year contract on 12 June 2019. Mainly a substitute during his spell, he scored ten competitive goals in 59 matches, including five in the 2020–21 edition of the Copa del Rey.

Valladolid On 31 August 2021, León signed a one-year contract with Real Valladolid. He scored seven goals in his debut campaign as the club achieved promotion to the top tier, adding six in his second and suffering immediate relegation.

Later career On 1 September 2023, transfer deadline day, León returned to Elche on a one-year deal. On 25 January 2024, he signed for SD Eibar as a free agent. He scored on his debut the following day, in a 1–0 win over CD Mirandés.

León joined amateurs Atlético Palma del Río CF in his hometown in September 2024.

Honours Individual Pichichi Trophy (Segunda División): 2015–16 Segunda División Player of the Month: September 2015