Pita Taufatofua defeated PNG's Steven Tommy 20-4 in the men's over 80kg division to qualify for his third Olympic Games and will be joined in Japan by Malia Paseka, 20, after the Pacific Games bronze medallist qualified automatically in the women's 67kg division.
"I'm feeling very relieved but also very happy that now Tonga is qualified for the Olympics...you know I just wanted to make sure that Tonga was represented at the Olympics and we can tick that box now," Taufatofua said.
The Brisbane-based athlete, 36, praised Paseka for becoming the first woman to represent Tonga in the sport on the biggest stage. He said she deserved all the accolades in booking her Olympic spot.
"Tonga Taekwondo have been trying since 1996 to 2000 to actually get someone to the Olympics. I qualified in Rio and now we also have a female to represent us as well and that's such a big deal for us, not just in Tonga but in the Pacific," he said.
"To have a female representing just makes me so happy. It is a dream come true to see a [Tongan] woman qualify in taekwondo."
Taufatofua, who rose to fame with a shirtless entrance at the 2016 Olympic Games opening ceremony, competed in the 2018 Winter Olympics in cross-country skiing and has one final chance to qualify for Tokyo in kayaking in May in his bid to become the first person this century to compete in three different Olympic sports.
His first attempt at the Oceania Canoe Sprint Championships last month, where he tried to qualify in the men's 200m single kayak event, was unsuccessful after suffering a major blow, forcing him to compete with rib and muscle injuries.
But Taufatofua said his injury was no excuse to quit on a sport he loved.
"The injury was very serious," he said. "It was a fractured rib and a torn serratus anterior muscle which had happened from me over training in kayaking a week and a half before the qualifier so I was in a lot of pain leading into that and then again leading into the taekwondo qualifiers."
"It did affect my race but I can't present any excuses you know whether I had a broken rib or my arm had fallen off, I always have to show up on the day and give my best and that time I fell short.
"I've lost many competitions, I've come last and I've come first but I've never quit on anything. I absolutely love the sport of kayaking and I will be racing in May. It's a long shot but I'm going to be definitely going for kayaking again."
Taufatofua is already training for the event, switching between the two sports in the lead up to the 2020 Olympic Games.
"Instead of having time off after the taekwondo qualifiers I was straight back into the kayak. I love the sport and I'm aiming to qualify for Tokyo in kayaking as well," he said.
Taufatofua's coach, Master Paul Sitapa, who moved to Australia to help coach the Tongan athlete said it had been an intense campaign.
"It's been quite intense for the last five or six months because we haven't been focused on one sport," said Sitapa.
"It's made the journey a little more challenging for us especially trying to manage time and training but we've finally made a spot into the Olympics."
Sitapa said their time at the Rio Olympics would always be special, but Taufatofua's drive to attempt new sports was opening new opportunities to inspire the next generation of Tongan athletes.
"It's still special because taekwondo is a sport we both know and love, but the experience in Rio has opened our minds to experience wider and to test our abilities not just in taekwondo but to approach other sports...by doing that, we believe the next generation will be able to do the same as well."
Sitapa added that having two taekwondo athletes competing at the games this year was a wonderful achievement for Tonga and for the women in sport.
"It's really amazing for what we're trying to achieve back home because we are not just doing this for ourselves," he said.
"Looking at the taekwondo in Tonga, we wanted to open up the doors and opportunities for the women in sport and we've never given up in training these guys...to get Malia to qualify through for this years Olympics, it's a big thing for us in taekwondo and also for the women of Tonga.
"Malia will be the first-ever female taekwondo Olympian for Tonga...to see Malia go through to the Olympics, it shows the women in Tonga that they can do it too."