Ratchanok Intanon
Marín began her 2019 season with a runner-up effort at the Malaysia Masters, where she lost to Ratchanok Intanon in straight games. On 27 January, Marín suffered a ruptured anterior cruciate ligament (ACL) injury during the Indonesia Masters final against Saina Nehwal, when she was 10–3 ahead in the first games. Marín subsequently retired from the match and underwent the ACL reconstruction surgery as soon as she was flown back to Madrid the same day. She had a recovery for four months, dedicate 10 hours a day to rehabilitation between the physical and technical, with morning and afternoon physiotherapy sessions, and swimming pool work.