Álvaro Mantilla Pérez (born 9 May 2000) is a Spanish footballer who plays for Racing de Santander. Mainly a central defender, he can also play as a right back. Born in Maliaño, Camargo, Cantabria, Mantilla joined Racing de Santander's youth setup in 2015, from Club Bansander. On 2 August 2019, after finishing his formation, he was loaned to Tercera División side CD Laredo for the season. Mantilla made his senior debut on 14 September 2019, starting in a 3–0 home win over UD Sámano. He scored his first goal as a senior the following 18 July, netting the opener in a 3–1 home success over CD Tropezón which helped his side to reach the finals of the play-offs; the club ultimately achieved promotion to Segunda División B after 30 years. Back to Racing for the 2020–21 season, Mantilla became a part of the first team squad also in the third division, being regularly used. On 20 March 2022, he renewed his contract until 2024, and was mainly a backup to Pol Moreno and Pablo Bobadilla as his side achieved promotion to Segunda División. Mantilla made his professional debut on 11 September 2022, starting in a 2–0 away win over Sporting de Gijón.