Nikki Hamblin of New Zealand stumbled and fell to the track. American Abbey D'Agostino tumbled over her, landing awkwardly. Just like that, their lives became forever linked and changed.
Their collision -- specifically, their reaction afterward -- was one of the most memorable and uplifting stories of the 2016 Olympic Games in Rio de Janeiro.
ESPN.com caught up with the pair a year later to find out what the two have been up to since their fateful encounter and what's next for these global icons of sportsmanship.
It was in the second preliminary heat of the 5,000 meters on Aug. 16 when Hamblin fell to the track of Rio's Olympic Stadium. D'Agostino, running behind her, may have clipped Hamblin's feet. Or Hamblin may have been thrown off by another runner. Neither is sure what happened in that split second.
"All I remember is running in the pack and I remember sensing something up ahead and not knowing what it was, but the next thing is, I'm on the ground," Hamblin said. "I've hit the ground pretty hard and I'm laying there wondering, 'What am I doing on the ground? How has this happened? What is happening?'"
She recalls D'Agostino standing over her saying, "Get up, we need to finish this." Although Hamblin has no memory of getting to her feet, both women mustered the will to continue.
D'Agostino, meanwhile, didn't realize she fell again later -- and was then helped up by Hamblin, who stayed close for a while, encouraging her -- until she saw video the next day.
Hamblin, shaken but having avoided major injury, was able to finish the heat in 16:43.61, more than a minute and a half behind winner Almaz Ayana of Ethiopia, the eventual bronze medalist.
When Hamblin turned to look back at the track, she was shocked to see D'Agostino still running. After helping D'Agostino to her feet with more than four laps left, she had assumed the American would have to stop. When Hamblin saw her in the final stretch, all she could think was, "Wow."
D'Agostino had torn the ACL in her right knee in the fall. Despite the pain, she'd kept running, praying the whole way.
"I didn't think she was going to finish," Hamblin said. "And yet she ran a mile with an injury."
When D'Agostino finished to loud cheers in 17:10.02, Hamblin met her with a hug.
"It was so special," D'Agostino said. "I think we both knew that what had happened was so crazy, but at the same time so beautiful. ... For both of us to be able to finish despite our dreams of what the race could have looked like, shattered, you know -- to just celebrate the good that came out of it -- that moment together was just unbelievable."
Race officials granted both runners spots in the final three days later, but D'Agostino was unable to compete and Hamblin, hampered by a sore ankle and Achilles tendon, finished last in the 17-woman field.
Their goodwill during their heat drew global attention. The two received the International Olympic Committee's Fair Play Award. President Barack Obama called D'Agostino's actions "exactly what the Olympic spirit and the American spirit should be all about."
"I say it sort of jokingly -- but sort of not jokingly -- like I could possibly still be lying on the track if Abbey had not done that," Hamblin said. "I don't know if Abbey hadn't done that whether I could have been able to get up and finish the race. [What she said] was that thing you need to bring you back into the real world instead of just being in shock. It was, 'Hey, get up, you have to get up and you have to finish and you have to honor what the Olympics is.'"
In February, they were reunited in Monaco for the Laureus World Sports Awards, where they were nominated for best sporting moment. They'd stayed in touch via email and texting, but the ceremony marked the only time they've seen each other since addressing the media the day after their race. This time they were in formal gowns for the ceremony, and they were able to share some downtime together, too.
"We forever will have sort of an unspoken understanding and connection because of the depth of what we experienced, not only in that moment, but also in the wake of it," D'Agostino said.
Hamblin: 'There's always a positive in everything'
Hamblin had hoped to compete in the world championships in London earlier this month, but that didn't happen. After taking three months off after Rio, she started training but suffered a foot injury in April.
"That's kind of ruled me out of racing for this year, but you know, I guess what Rio taught me is there's always a positive in everything, you just have to find it," she said.
She has dived into what she calls her first "grown-up job," working in membership for Cycling New Zealand. Living in the North Island town of Cambridge, she's enjoying being in a professional office environment for the first time and having a different focus. The 29-year-old also will complete her long-delayed sociology degree this fall. Although she can't run, she can cycle and will soon take part in her company's corporate challenge race.
"A goal for this year was to be in London at the world champs and be on that start line, but instead I'm going to be on the start line of a corporate pursuit," she said, laughing.
Once she's healed, she'll start training again with the goal of getting to the 2020 Olympics in Tokyo. After an Achilles tendon injury took her out of contention for the 2012 London Games, and then the Rio incident, the four-time New Zealand champion in the 1,500 meters and two-time Commonwealth Games silver medalist hopes she'll finally be able to compete without injury or mishap.
Though she wants to win an Olympic medal -- a dream since she was 15 -- she understands she has already done something special at the Games.
"The further time comes between the incident," she said, "when I can separate some of the sadness around it, I understand, 'You actually did a good thing.'"
Though Hamblin says she'd eventually like to be known for more than being "the girl who fell over," she's now comfortable talking about what happened. She laughs easily and sees the positives.
"My result on the track doesn't define who I am as a person," she said. "When I was growing up, my dad would always say to me, 'It's not about the destination. It's about the journey.' ... I didn't understand, like, 'What do you mean?' But Rio, now I get it. I get that quote and I understand what it means. I'm excited because it's changed the way I look at my running. ... I can find positive things about other areas of my life."
D'Agostino: 'I don't regret anything that happened'
The last time D'Agostino, a seven-time NCAA champion, competed on a track was that race in Rio. She had surgery to repair the ACL and meniscus in her right knee, then returned to training in March and April. But she strained her right hamstring, sidelining her again.
This fall, she expects to enter some cross-country or road races, with a return to the track next year.
"It's been more of two steps forward, one back, which I'm learning is what I should expect in the 18 months after surgery," she said.
Yet even without running, the past year has been good. She got engaged in June and will be married next summer. Also in June, she was presented with the honorary degree of Doctor of Humane Letters by Dartmouth, her alma mater, for her "gold standard" of sportsmanship.
D'Agostino also has taken joy in sharing with people -- in speaking engagements and at clinics -- what she experienced in Rio.
She says a confluence of factors related to her faith primed her for what happened that day. She had several pre-event talks about faith and miracles in the athletes village with Team USA chaplain Madeline Manning Mims, a former Olympic gold medalist, who spoke about how she had once been able to finish a race despite a serious injury.
Ten days before her race, D'Agostino also took part in a Bible study about the power of miracles. And before she stepped to the line for the 5,000, she wrote part of a Bible verse on her hand in ink, something she's done before. This time, it was "Now to him who is able," a piece of Ephesians 3:20: "Now to him who is able to do far more abundantly than all that we ask or think, according to the power at work within us."
"Because of so many things that were working in my life to prepare my heart to respond that way, I was able to show off the character of love and sacrifice that is natural only to God," she said.
Now, D'Agostino, 25, has much to look forward to. She was disappointed she didn't have a chance to compete for a medal in Rio but believes she'll get more chances. She's just grateful for the experience.
"Just to have that opportunity, to be on that stage, was incredible," she said. "So I don't regret anything that happened."
And she now sees running as more of a path than a destination. Like Hamblin, she views running as a wonderful part of her life, but not her entire life.
"It's just a vehicle for me to put on display the athletic and the mental and all the gifts and resources I've been given to be able to do this sport," she said. "It's a better, more mature life balance, I think. I'm developing a more sustainable relationship with the sport."