The three-time Olympic silver medallist and former world number has been on the sidelines since July last year when he was diagnosed with early-stage nose cancer.
The Spanish badminton federation said Marin would undergo surgery on Tuesday and start rehab next week for an injury that typically requires a recovery period of at least six months.
Antonsen, who was not accompanied by his coach, reached the final of the the championship for the first time and managed to upset Momota 21-16, 14-21 and 21-16 in a game that lasted one hour and 19 minutes.
The relatively unknown player beat two-time Olympic champion Lin 21-19, 21-18 to win the Thailand Masters at the weekend.
Lee stopped playing in the middle of last year after he discovered he had cancer in July.
Sindhu, 23, has suffered a series of near-misses in recent years, winning silver at the 2016 Rio Olympics, and again at the Asian Games and Commonwealth Games this year.
The sixth-ranked Indian will play Japan's Nozomi Okuhara in the final.
The all-action Japanese star powered past Indonesia's Tommy Sugiarto 21-14, 21-8 in just 36 minutes in the Chinese city of Guangzhou.
The 23-year-old, a silver medallist at the Rio Olympics in 2016, faces Zhang Beiwen of the United States on Friday.
Women's number one Tai Tzu-ying from Tawian defeated Zhang Beiwen of the United States.
The three-time Olympic silver medallist said the cancer was detected following a check-up in July, after he had been unwell.
The three-time Olympic silver medallist, who has spent nearly five months on the sidelines, is already doing light fitness work after receiving a clean bill of health from doctors, Malaysia's badminton chief said.
Gaya, from Mauritius, had since 1999 held positions with the Badminton World Federation (BWF), the Badminton Confederation of Africa and the Mauritius Badminton Association (MBA).
Widely known as "Super Dan" during his pomp, the 35-year-old Chinese last week suffered his ninth first-round defeat in 19 tournaments this year, underlining his steep decline.
Both players were hungry for the win, drawing level 13 times in the second game before the sixth-ranked Okuhara beat the Thai, a former world champion, 21-19, 24-22 in 64 minutes.