The Spanish history-maker was smiling and looked fresh as she spoke by video call to Spanish sports daily Marca about how she's ready to turn the page on 2020 and is looking forward to 2021.
"I've had moments of doubt and fear, with the injury you ask yourself if you can really go back and compete and actually win a game. I have to thank every single member of my team."
"Despite everything that's happened I want to turn things around and get back to being Carolina the fighter, to believing in myself so I can really go for my aim of winning gold in Tokyo," she tells Marca.
"Winning a silver medal wouldn't satisfy me and I'm very headstrong in that respect. I've never even thought about what might have happened if I hadn't won gold in Rio 2016."
Carolina Marin: Being the best
Ever since she was 14 Marin has known what she wants: To be the best badminton player in the world.
At 14 she and her family moved from her hometown of Huelva to the high-performance Olympic training centre in Madrid.
There, she joines coach Fernando Rivas and the team that would help take her to the top.
"I'm surprised by how far I've come but while I'm doing it I don't even think about it. I have complete trust in my team, but there are days you get into bed and even your eyelashes hurt."
That team includes head coach Fernando Rivas, assistant Anders Thomsen, physiotherapist Diego Chapin, fitness coach Guillermo Sanchez, technical team Ernesto Garcia, Maria Martinez who is Carolina's sports psychologist, her personal pychologist Fany Barembaum, head of press Ignacio Paramio Gomez, and her representative Ignacio Garcia.
Badminton singles may appear to be an individual sport on the court, but off it it's a team game.
Rivas, who spoke with Marin on the videocall, likes to remember the first world championship that Marin won at Copenhagen 2014 when they turned the hotel room into a war-room complete with a curtain transformed into a cinema screen using a projector to analyse all of Carolina's opponents.
"We were exhausted, we were up until 4am preparing the analysis," says Rivas, "when Carolina came into my room she said "but what's all this!?""
On the attack
Despite a glittering career that includes Olympic gold, three world championships, and four European titles, Marin still wants more.
And more means adapting and evolving, "you mature and improve", says Carolina, "every year we train new things."
Rivas has some new ideas focusing on the superstar shuttler's offensive game.
"We want to improve her strategy of attack but it isn't easy. Sometimes the decisions aren't the best suited because some of our patterns are already well known in the game."
Whatever the new strategies her team come up with, there can be no doubting Marin's dedication and professionalism, and now she says she feels refreshed, happy, and ready for what's next.
"It's true that I've been through some hard things... But for me it's a year to turn the page and look forward to 2021. It's exciting to have two big goals that motivate me."
Those two objectives are clear: Four years ago she became the first Spaniard to win badminton gold, at Tokyo 2020 in summer 2021 she can become the first to retain it.
Then in November/December 2021 she has a chance to win a fourth world championship in front of an adoring crowd at a stadium that's been named after her in her home town: The Palacio de los Deportes Carolina Marín in Huelva.
As if she needed any more motivation.