Quintero made his first appearance of the 2018 Clausura on 7 January, recording an assist in a 1–0 over Querétaro. During a training session on 23 January, Quintero tried to shoot a ball at a reporter who was on live TV. Although Quintero denied that his intention was to hit the reporter, América announced they would sanction him internally. After missing three matches, Quintero came off the bench in a 4–1 win against Morelia on 13 February. His next appearance came on 28 February as he scored once in a 1–1 draw with Deportivo Saprissa in leg two of the round of 16 of the 2018 CONCACAF Champions League. América advanced on aggregate by a score of 6–2. He would appear in both legs of the quarterfinals as they advanced past Tauro, with Quintero picking up an assist in the second leg, which would end up being his final appearance for the club. His time with América was mixed with success and disappointment. He helped the club win trophies, but was also seen as not living up to his price tag, as fans were critical with his inconsistency. He was even booed off the pitch at times by América fans.