Veteran Chinese radio DJ Eeva Chang Mei Hsiang, who has organised the Singapore preliminaries of the contest, debunks the theory by sceptics that it is the production team's strategy to increase ratings among overseas viewers.
"The four mentors are established in the music industry. They need not pick contestants if they are not up to standard.
"Viewers also have expectations," she says, referring to the show's four mentors - Chan, Jay Chou, Na Ying and Liu Huan.
Instead, she, along with other industry observers, believes that Hartono's stellar performance on the show last year paved the way for his fellow countrymen.
She adds: "Naysayers used to diss the idea of Singapore contenders competing against the Chinese. Nathan proved them wrong - we can hold our own in the singing competition."
Singapore's language and culture diversity could just be the winning edge for its singers.
Mr Jay Lim, 38, principal of Lee Wei Song School of Music, says the country's melting pot of cultures and languages has influenced musicians here.
He adds: "We are able to perform a song, arrange it in a way that is refreshing to the Chinese audience. It is not just about seeing who can hit the highest note."
And not just in China either. Over in South Korea, aspiring K-pop star Tasha is competing for a chance to debut in a girl group on a survival reality show, Idol School.
Singaporean singer-songwriter Yong Bang, 42, says: "We subconsciously absorb information from all over the world and various cultures. That is our advantage."
For Sing! China's four Singapore challengers, the support they provide one another gives them another boost.
Dong says: "It's comforting to be able to break into speaking Singlish whenever I meet a fellow Singaporean in the competition.
"When we do, the other competitors usually give us quizzical looks and ask us if we are speaking in English.
"It's not meant to be divisive, but when you're far away from home, small things like that help you cope with the loneliness and stress of the situation."
• Sing! China airs on Jia Le Channel (Singtel TV Channel 502) on Fridays at 9pm, the same time as in China.
Winning is not a key factor
SINGER STELLA SEAH, 24; TEAM NA YING
Contestant Seah wants to make an impression in the Sing! China contest, not for the sake of winning, but so people know she is still in show business.
"After releasing my album, I did not have many chances to sing on television, so not many people know that I am still active," says Seah, who is signed to local label Ocean Butterflies and released her Mandopop EP Wings Of Dreams in 2014.
"I want people to know that Stella Seah is still pursuing her dream. I hope people will remember me, my face, my name."
During the blind auditions on the Sing! China stage, she made an impression with vocals as bright as her personality. The cherubic singer won the vote of mentors Na Ying and Eason Chan with her "cheery" performance of Richie Jen's mid-tempo tune, I Am A Fish. She went with Na.
Although her long-time Mandopop hero Jay Chou did not pick her, she is not disappointed as she went on the show without expectations.
"This isn't my first time joining a singing competition. I have grown along the way and learnt that winning or losing is not a key factor for me," says Seah. She took part in 2007's Campus Superstar, a televised singing contest for students, and emerged tops on StarHub TV singing contest Sunsilk Academy Fantasia in 2012.
"I want to hear singers from all over the world and learn from the best people in this industry."
She says of award-winning singer Na, who has given each member of her team a customised T-shirt: "She not only taught me singing, but also danced along with me while I sang. I thought she would be very stern, but she turned out to be so fun and motherly."
Away from home, Seah - the younger of two daughters - counts on her fellow Singapore contestants for support.
"I spend more time with Curley (Gao) because we are in the same team. Joanna (Dong) gave me snacks from Singapore. Olinda (Cho) gives us hugs and verbal encouragement from time to time.
"I text them occasionally to cheer them on. I would hate to battle a fellow Singaporean. I don't want to think about it now."
Putting up a good fight
SINGER OLINDA CHO, 37; TEAM JAY CHOU
She is 37 this year and Cho was filled with self-doubt, wondering if she was too old to compete in a singing contest such as Sing! China.
Her insecurity stemmed from not getting picked to join the show last year, after winning the chance to represent Singapore on that platform.
She says: "Because of what happened last year, I felt maybe I was just not good enough. I even asked the producers if it was because I was too old. They said no."
Called back by the producers for a second shot this year, she convinced herself that age is just a number.
She says: "I went to conquer my fear. I'm 37 and have nothing to lose and everything to give. If they give me a chance to sing, I will not leave without a good fight.
"My game plan is to sing every song like it's the last song I'll get to sing."
With the support of her parents and younger brother, who flew to Hangzhou to cheer her on at the blind auditions this year, she had three mentors - Jay Chou, Na Ying and Liu Huan - who wanted to recruit her to their teams.
Eventually, she picked Taiwanese star Chou, who said he would give her the freedom to express herself.
Now that she has had a chance to train with him, she says: "He is easygoing, open to suggestions and so encouraging. Every day, he tells me not to worry, to just be myself and do my thing. It's very reassuring."
As she is on the same team as fellow Singaporean Dong, Cho dreads the day they will have to compete against each other.
She says: "It's too cruel. We are a team. We are as one. I don't see her as a competitor. I'm lucky to have a fellow Singaporean on this journey with me."
Sharpening her tools
SINGER-HOST JOANNA DONG, 35; TEAM JAY CHOU
Dong pulled out all the stops during the blind auditions, impressing the mentors with her lilting voice, scat singing and mouth trumpet.
I have no more new tricks, but I'm working on sharpening the tools I already have... My goal isn't to win, it is to push myself further.
SINGER JOANNA DONG
She says: "I don't have a game plan. I'm not a particularly good strategist. My initial goal was just to make it past the blind auditions, that's why I threw out all my 'weapons' in that first round."
Her straightforward strategy worked. Barely a minute into her jazz rendition of the Lo Ta-yu classic Love Song 1990, judge-mentor Jay Chou wanted her on his team. As he immersed himself in her performance and nodded along to the music, coaches Eason Chan and Liu Huan wanted to recruit her as well.
Her glowing reception at Sing! China - which she is participating in for the first time after being scouted by its producers - is a far cry from her experience at the inaugural Singapore Idol in 2004.
Scarred by the widespread criticism that came with appearing on a televised contest, she stayed away from mainstream limelight and went on to make her name in the theatre and jazz scenes here.
In 2008, she won the Best Supporting Actress award at The Straits Times Life! Theatre Awards for her role in the Mandarin musical, If There're Seasons. She has also released several singles and an EP, Lullaby Nomad (2008).
On Sing! China, she has reunited with Singapore Idol alumnus Olinda Cho, who is also on the Taiwanese pop star's team.
"I didn't get to spend as much time with Olinda back in the Singapore Idol days because I was eliminated at the Top 40," says Dong, who is married to a School of the Arts Singapore teacher. They have no children.
"This time, Oli and I have the chance to have intimate conversations and get to know each other much better. It's more than a decade late, but well worth the wait."
Moving forward in the competition, she says: "I have no more new tricks, but I'm working on sharpening the tools I already have. If I do a trumpet again, I've got to make it slicker. If I scat again, it will have to be more confident. My goal isn't to win, it is to push myself further."
Celebrating her birthday with her mum's idol
SINGAPORE-BASED CHINESE STUDENT CURLEY GAO, 19; TEAM NA YING
Dunman High student Gao says she will forever remember the day she turned 19 this year. Chinese singing star Na Ying surprised her with a birthday cake during their first rehearsal for Sing! China in Beijing last month.
She says: "I never imagined she'd take the time to celebrate my birthday, together with the rest of the team. It was so touching. I can say it is the best birthday I've had."
During the blind auditions, she had chosen Na over Hong Kong singer Eason Chan to be her mentor in the popular singing contest.
"My mum could not believe her idol would be my mentor. Growing up, my mother used to play Na's classics and I would listen to songs such as Conquer," says Gao, a Chinese national who has been studying in Singapore since the age of nine. She is an only child living here with her mother, a retail trader, and her father, a senior pharmaceutical consultant.
Her rendition of Incomparable Beauty, a melodious ballad by Taiwanese indie band sodagreen, during the auditions also impressed Taiwanese star Jay Chou. Although he did not ask her to join his team, he compared her vocals with that of acclaimed Singaporean singersongwriter Tanya Chua.
This is Gao's second shot at the blind auditions. Last year, she earned a chance to sing onstage in China after taking part in auditions held in Singapore, but was not picked by any of the judges.
The producers invited her back this season.
Now Gao is glad to have the company of three other singers from Singapore.
"When we hang out, Singlish comes out naturally, it's so comfortable interacting with one another. We don't see one another as competition. Instead, we have become close friends who cheer one another on," she says.
"It would be interesting to compete against one of them. But even if I lose, I know my opponent will do Singapore proud."
A version of this article appeared in the print edition of The Sunday Times on August 13, 2017, with the headline 'Singing for Singapore'. Print Edition | Subscribe
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