is a Spanish professional football manager and former professional player who is currently the head coach of the Portugal national team.

Martínez played as a defensive midfielder and began his career at Real Zaragoza, with whom he won the Copa del Rey. He spent a year at lower league side Balaguer, before signing for English Third Division side Wigan Athletic. Becoming part of a small Spanish contingent at the club known as \"the three amigos\", alongside Jesús Seba and Isidro Díaz, he was a regular first team player for six years, the longest period of time he spent at one club. During his time there, he won the Football League Third Division and the Football League Trophy. He moved to Scottish side Motherwell, then to Walsall, before joining Swansea City in 2003. He became club captain and helped the team to win promotion to League One in 2005. He moved to Chester City in 2006, and was again chosen to be captain.

In 2007, Martínez began his managerial career at Swansea City and led the club to Championship promotion as League One champions. He then joined Wigan Athletic as manager in 2009, helping the club avoid relegation for three consecutive seasons. In his fourth season Wigan were relegated, but won the FA Cup in 2013 for the first time in the club's history. At the end of that season, he became manager of Everton, finishing in fifth place in his first season at the club. In May 2016, he was dismissed as their manager with the club in 12th position, and became Belgium's head coach in August 2016. Martinez guided them to third place in 2018 FIFA World Cup, their best-ever position in the competition, as well as holding first place for Belgium in the FIFA World Rankings from 2018 to 2022. He resigned from Belgium after the 2022 FIFA World Cup. In January 2023, he was appointed as the head coach of Portugal.