Pain flashed through Tatjana Schoenmaker's groin as she prepared for her last Commonwealth Games race this week, and her coach feared the chances of a golden double had evaporated.
The 200m breaststroke champion's pain started during the 100m breaststroke semifinals and flared up again just before the final.
"In the warm-up she said to me, 'no, it's still sore'," coach Rocco Meiring recalled this week. "She's never taken a painkiller before she raced, but she took one this time." And she won gold again, in the 100m.
It should have been tickets for the shy 20-year-old University of Pretoria BCom student, but she had one trump card left.
"I relied on her fighting instinct," said the coach, who has seen her race boys "stukkend" [broken] in training.
At last year's university championships, his Tuks team was lying second and he had nobody to swim the 800m freestyle decider, so he called on Schoenmaker. She beat distance specialists to clinch the gala."She's like a racehorse, she doesn't like somebody next to her," he said. "Don't be fooled by that sweet smile. She's tough."
Schoenmaker was a revelation in Gold Coast, taking the breaststroke double and breaking African records.
The 2min 22.02sec she clocked to win the 200m - good enough for bronze at the Rio Olympics - surprised even herself and Meiring. Particularly impressive was her strength on the final lap, coming out the last turn in second spot and powering to an easy victory.
Former Olympic breaststroke queen Penny Heyns was inspired. "I'm impressed with her back-end speed ... Very tough. If she continues to improve at the same rate and margin then certainly she will rate among the [2020 Olympic] medal contenders."
The caterpillar has transformed into a butterfly, but Meiring said Schoenmaker was no overnight success.
Women's swimming in South Africa has produced only nine able-bodied Commonwealth medals since readmission, compared with 32 men. Just 12 women aged 20 and older competed at the 2017 SA champs.
"We lack adult, mature swimmers, so what we do is push the youngsters and we can push the girls sooner than the boys because the girls mature faster."
The focus switches to high intensity, but the gains are short term. "You start pushing the intensity too early, and you skip the step of laying a good endurance foundation."
It's almost impossible to go back and do it again, said Meiring.
Midway through our interview at the athletes' village Schoenmaker arrived, with the team's media liaison officer announcing: "The Golden Girl is here."
Meiring replied with a wry smile. "That's not Golden Girl, this is Troubles."
Why does he call her that? "I don't know," Schoenmaker responded: "I'm innocent."
Meiring recounted how Schoenmaker first struggled to adjust to the Tuks high school; she had wanted to stay at her previous school with her friends and play netball.
"Now I will say it's the best decision ever," she said. "But at that time I really didn't want to swim. If I overslept I'd get a call from Rocco and then literally two minutes later from my dad because Rocco phoned my dad and I'd be in the biggest trouble ever."
The weekend before the Games she was still in hard training, in tears from the pain. "I had to remind her 'your body has to remember what it feels like when you go into the 200'," said Meiring. "Even though she was crying she stuck to it. No drama."
Schoenmaker has previously talked herself down, but is speaking more freely about her ambition. "My biggest dream is winning gold at Tokyo, since I was little.
"Now that I've gone gold at Commonwealth I think I feel more motivated and more encouraged to believe in myself."
The butterfly is ready for lift-off...