 He featured five times for the U20s at the 2016 U-20 Copa Libertadores in Paraguay, which preceded a loan spell to Primera B Nacional's Brown for the 2016–17 campaign.He made his professional debut on 28 October 2016 in a 2–1 loss against Estudiantes, prior to scoring his first senior goal in June 2017 versus Villa Dálmine.In total, Martínez played fourteen times and scored once for Brown.