Both players earned relatively straightforward semi-final wins today at Impact Arena in the BWF World Tour Finals, with the Spaniard having the advantage of playing home hope Pornpawee Chochuwong when the latter was hampered by an ankle injury.

Marín took full advantage as she advanced with a 21-13, 21-13 victory.

Tai knew too much for the talented 18-year-old from South Korea, An Se-young, who had beaten Marín in her final group match the day before - albeit that Marín was experimenting with some new shots in a match that was a dead rubber for her.

The Chinese Taipei player earned her place in the final with a 21-18, 21-12 win.

Meanwhile the men’s top seed Viktor Axelsen secured a place in tomorrow’s men’s singles final with a 21-16, 21-9 win over Chinese Taipei’s third seed Chou Tien Chen, and will now meet fellow Dane and second seed Anders Antonsen, who beat Chou’s compatriot Wang Tzu Wei 21-18, 14-21, 21-16.

By a quirk of the draw, both men’s semi-finals were action replays of the final group matches, with Axelsen replicating his result and Antonsen exacting revenge for defeat.

Marín is full of confidence as she looks ahead to what could be a historic win.

"My performance today wasn’t too bad, I told myself before entering the match that I needed to play patiently because An Se Young is a player who doesn’t make mistakes easily," Tai told the BWF website.

"I hope that I can prepare well for tomorrow’s final.

"Everyone is tired because we’re in the third week and I just wish to focus now and be patient."

Marín commented: "I could show my determination on court that I wanted to win today and I did, and I’m happy with my performance.

"Tai and me will play our third final in a row, so it’s tough but I’m looking forward to the final.

"It’s going to be one more game, we played two weeks ago and a week ago, and tomorrow’s a new day, a new match, and it’s going to be different.

"She’s playing well, but I think it’s been tough for her because she lost more games than me.

"She’s looking a bit tired, I think.

"Let’s see how the match goes."

Meanwhile Indonesia’s Mohammad Ahsan and Hendra Setiawan have moved to within one win of successfully defending their men’s doubles title after a 23-21, 21-13 win over South Korea’s Cho Sol-gyu and Seo Seung-jae.

But, like Marín, their opponents in tomorrow’s final, Wang Chi-lin and Lee Yang, are targeting a third successive title.

The Chinese Tapei pair beat England’s Ben Lane and Sean Vendy 22-20, 21-17.

The women’s doubles final will be an all-South Korean affair between Lee So-hee and Shin Seung-chan, who beat Malaysia’s Chow Mei Kuan and Lee Meng Yean 21-14, 21-15, and Kim So-yeong and Kong Hee-yong, who had a 21-11, 12-21, 21-16 victory over home pairing Jongkolphan Kititharakul and Rawinda Prajongjai.

Home pairing Dechapol Puavaranukroh and Sapsiree Taerattanachai reached the mixed doubles final with a 21-15, 21-17 win over France’s Thom Gicquel and Delphine Delrue.

Their opponents will be South Korea’s Seo and Chae Yu-jung, 21-19, 21-8 winners over Malaysia’s Goh Soon Huat and Lai Shevon Jemie.

The BWF World Tour Finals is the third of three tournaments taking place in a bubble in Bangkok.