Martínez started his career with El Tanque Sisley.[1][2] He scored on his professional debut, netting in a 2–1 victory in the Uruguayan Primera División over River Plate on 7 May 2011; another goal followed three weeks later against Miramar Misiones.[1] In total, he featured ninety-three times in all competitions during three years with El Tanque Sisley.[1][3] Martínez had a seven-month stint with Cerro, prior to joining fellow Primera División side Rentistas in July 2015.[1] Twenty-three appearances followed across the 2015–16 season, which ended with relegation to the Uruguayan Segunda División.[1] On 28 February 2017, Martínez rejoined El Tanque Sisley.[1]
After nineteen appearances in the top-flight for El Tanque Sisley, Martínez departed to complete a move to Sud América in February 2018.[1][4] Manager Gustavo Bueno selected the midfielder twenty-five times in his debut campaign with the club.[1]