Martínez was in charge of Guatemalan club Xelajú in 1996, and became an assistant of Roberto Fleitas at Nacional Montevideo in the following year.
He subsequently worked in the youth sides of Fénix before being named manager of the first team in January 2010, replacing Julio César Ribas.
[8] After leaving Fénix at the end of the 2016 season, Martínez was named in charge of Liverpool Montevideo on 5 September 2017.
[9] Dismissed on 4 December,[10] he spent more than a year without a club before taking over Rampla Juniors on 4 March 2019.
[11] Sacked by Rampla on 19 August 2019,[12] Martínez retired shortly after due to heart issues.