17 years, 5 months and 24 days old, older only than Daniel Villalva, Adolfo Pedernera and ex-Barcelona and Real Madrid player Javier Saviola. After his debut, Cappa excluded him in the match against Huracán, but he replaced the suspended Ariel Ortega in the next game against Independiente where he assisted Rogelio Funes Mori's goal for the 3–2 victory. In a match against Vélez Sársfield on 5 September, Lanzini suffered an injury after a tackle from Leandro Somoza, which ruled him out for three weeks. He made his comeback to the first team on the 12th match of the season. Fluminense (2011–12 season) On 19 July 2011, River Plate agreed to loan Lanzini to Fluminense for a fee of US$400,000, with a transfer option of $15,000,000. Lanzini made his debut in the Brasileirao 2011 for the 3–0 victory against Figueirense. He would then score his first official goal in the team's 20th game of the tournament, a 2–1 victory against São Paulo. His performances and character led to the club's president labelling him "the new Neymar". His most important goal for the club was against Flamengo in the Río de Janeiro Fla-Flu derby. Despite Lanzini's good performances, Fluminense was unable to retain him and he returned to River Plate after the loan expired. Comeback to River Plate and consolidation 2012–13 season Lanzini returned on 30 June 2012. He started for the team's first appearance in the tournament, scoring their only goal in the 1–2 loss against Belgrano de Córdoba. For his comeback, he asked his coach Matías Almeyda if he could use the club's iconic number 10 shirt, which Almeyda approved. However, during Almeyda's term Lanzini was unable to assure himself a place on the pitch, sometimes watching the matches from the bench. Almeyda was fired and the club's most successful coach to that date, ex-Inter Milan player Ramón Díaz, was appointed as team manager. With him, Lanzini's chance of regaining a place as a starter increased. Diaz made Lanzini a starter in the team's 2–0 victory against San Martín (SJ), where he scored one goal. He was then considered a regular starter for the team. During the 12th match of the Torneo Final 2013 tournament, he scored his first goal in the Superclásico, one of the most heated football rivalries in the world, in the 1–1 draw against Boca Juniors; this goal, as of 2018, stands out as the fastest