If this is the end, at least she goes out on her terms, with an Olympic silver medal to hang alongside her 2012 Games heptathlon gold.
Jessica Ennis-Hill is relaxed, smiling, perhaps even content, the day after completing her event at the Rio Olympics, finishing behind Belgian Nafissatou Thiam.
There might be a stab at next year's World Championships in London but no more after that. The Tokyo Games in 2020 are out of the question, she tells The Straits Times on Sunday in Brazil during an interview organised by Omega.
The 30-year-old Briton, who is a brand ambassador for the Swiss luxury watchmaker, said: "I definitely won't be going to Tokyo unfortunately. It's a stretch too far for me.
"Four years is a long time to prepare. It's a lot of training, a lot of dedication. I have had a long time in this sport already, so these Olympics here are definitely my last.
"It's been an incredible two days of competition and I would have loved to have come here and defend my title but I performed the way I could, as hard as I could have and to win a silver medal is great."
If she sounded fulfilled even without a golden send-off, it is because she was.
Motherhood - her son Reggie turned two last month - will occupy her and retirement will bring with it time, a precious commodity for someone who for the past two decades has had her life ruled by the stopwatch and alarm clock.
Time heals wounds and Ennis-Hill has had quite a few.
She missed the 2008 Beijing Games after stress fractures of the navicular and a metatarsal in her right foot - which kept her out of action for 12 months - and she has "had Achilles problems over the past few years, torn my calf a couple of times on both sides and had injury setbacks throughout the year" that hampered her preparations leading up to Rio.
Reflecting on hanging up her spikes, she said: "When I do make that decision, it's going to be tough because like you said, I've trained my whole life and I've competed for such a long time. So I'll definitely miss it but there are elements of me that look forward to the next chapter of my life.
"I do want to stay involved in sport and want to keep active," she noted, before that mega-watt smile broke out as she added: "But being a heptathlete, the training is tough so I won't miss all of that."
Britain will certainly miss Ennis-Hill. She and middle-distance runner Mo Farah, along with long jumper Greg Rutherford, have been at the forefront of British athletics, winning five Olympic titles and eight world championships between them.
This is likely to be their final Summer Games outing and Saturday night, when all three competed at the Olympic Stadium, was especially poignant.
"I haven't yet had a picture (with them) but I did see Mo after I ran and saw his (gold) medal and spoke to Greg after he got his (bronze) medal," Ennis-Hill said.
"It's nice to see them and see how well they've done and great (that) we've come back four years down the line and all won medals again."
Even when she makes her eventual exit, Ennis-Hill hopes to continue the fight against doping.
She said: "It's not naive (to think sport can be free from doping) because we have to keep working towards it. It's in the best interest of the athletes; we can't just let this happen.
"This year has been a tough year with all the doping scandals that have come out but at least they're coming to light and we know what's going on and action is being taken now because there are so many athletes that train for years and years but they miss out on medals because people have cheated them out of medals and it's not right.
"We train so hard and it's about athletes performing truly and doing it clean. So I hope we keep fighting against this and making our sport as clean as possible."