Marin, the current world champion, recovered from an early deficit to record a hard-fought 19-21, 21-12, 21-15 triumph.

In the second final to take place on day 14 at Rio 2016, China's Fu Haifeng and Zhang Nan, a mixed doubles champion at London 2012, took the men's doubles crown as they ensured Malaysia's wait for an Olympic gold medal went on by beating Shem Goh and Wee Kiong Tan 16-21, 21-11 23-21.

Marin, the current world number one, came into the contest with her Indian opponent as the favourite but would have been wary of Sindhu's prowess at major tournaments as she has two World Championships bronze medals to her name.

The Spaniard began the better of the two players but the 21-year-old Indian gradually grew into the match after a nervous start and managed to stun Marin by edging the first game.

Sindhu, bidding to become the maiden Indian player to seal an Olympic singles gold after Saina Nehwal claimed bronze in London 2012, was not able to match her performance from the opener in the second game as Marin began to take control.

The 23-year-old from Huelva, already a two-time world and European champion, used her vast array of shots to draw level and sent the gold medal encounter into a decider.

It proved to be a tense affair as both players, who have been in excellent form throughout the Olympic tournament, appeared tense.

At one point, the score was locked at 10-10, leaving the contest finally poised, before Marin took the initiative and displayed the qualities which have seen her dominate the women's game in recent years on her way to a momentous victory.

The bronze medal match was won by Nozomi Okuhara of Japan after Chinese opponent Li Xuerui, gold medallist at London 2012, withdrew before they got underway.

"I can only say there is a lot of work behind that - it was really tough two months ago," Marin said. 

"In every training, I just wanted to think about the medal and that I wanted to fight, and today the dream is coming true.

"I just wanted to enjoy every moment of this final. 

"At the end of the first set, she made some tactical things but I think the key for this final was to believe in myself. 

"To remember that if I wanted to get the gold medal I had to give everything and I did."

The men's doubles final was also a dramatic affair as the Chinese pair of Fu and Zhang emerged victorious despite dropping the opening game.

They were not at their best early on before they restored parity, though they looked consigned to the silver medal when the Malaysian duo of Shem and Wee had two match points.

Unfortunately for the Malaysian competitors, it was not to be as the Chinese team ground out the win.

Britain's Marcus Ellis and Chris Langridge secured their country's first Olympic badminton medal for 12 years when they overcame Chai Biao and Hong Wei 21-18, 19-21, 21-10 yesterday.