 In September, after eight-month break forced by the injury, Marín returned to competition at the 2019 Vietnam Open, but suffered an opening round defeat to Supanida Katethong.However, she was able to bounce back and, on 22 September, she won the China Open, defeating Tai Tzu-ying in the finals with a score of 14–21, 21–17, 21–18.This was Marín's first title of the season, which she followed with the semi-finals at the Denmark Open, where she was defeated in three tight games by Nozomi Okuhara.