By the 29-year-old's own admission, the hilly course wasn't ideally suited to her, and she was worried about how she might fare on the climbs.
But Fahlin found herself on the attack as part of the day's main breakway, before the Netherlands' Anna van der Breggen made what turned out to be the winning move.
"I had to dig so deep on the last lap, and I'm totally spent now," Fahlin said at the finish. "I knew that this course would be too hard for me, and I was a bit worried about the first steep climb, but I managed to get over it.
"I tried to get away a couple of times, but it didn't stick. I was dropped at one point on the main climb, but I got back on with another couple of girls, and then I went with a move straight away when I got back, just passing the bunch. It was a couple of other girls probably thinking like I did, and it was good that we could co-operate."
With just over 40km to go, Fahlin was still at the head of affairs with the USA's Coryn Rivera, Elena Pirrone (Italy), Ellen van Dijk of the Netherlands and Poland's Malgorzata Jasinska.
However, once Van der Breggen steamed into the lead, Fahlin was dropped, but managed to find a second wind and finish first of the non-medal places.
"This is my best result at the Worlds, which I never expected on this course, as this is probably a course least suited to me," Fahlin admitted. "But I've improved this past year, and sometimes it's about making the right move and trying to believe that you can still be in the race somehow, and I think today was proof of that.
"The Worlds are always a bit special with tactics and everything, so it worked to be in the race today."
Niewiadoma happy to finish her season on a high
"It was a hard race with a lot of different situations, and I didn't actually know what to do, or how to react," Niewiadoma said. "I had a teammate in the break [Jasinska], and most of the riders in our 'little peloton' had someone at the front, so no one wanted to chase it."
She eventually finished as part of a 14-woman group, over seven minutes down on winner Anna van der Breggen of the Netherlands, and was left to reflect on her season.
"A lot of people think I had a bad or difficult year, but to be honest I don't consider my year to have been that bad," said Niewiadoma, who scored wins at the Trofeo Alfredo Binda in the spring and the overall title at the Tour de l'Ardèche earlier this month.
"Of course, I perhaps didn't get the results everyone was hoping for, but personally I'm okay with my shape. There was just always something missing, but maybe it was just in my head," she admitted.
Asked whether the Polish men's team – which includes Rafal Majka and 2014 world champion Michal Kwiatkowski – would now quiz her about the course for Sunday's men's race, Niewiadoma said that she had just enjoyed being able to hang out with her national teammates.
"For sure they'll ask about the course. I really like to talk to my federation, as I don't get too many opportunities to spend time with the Polish riders, and it's kind of different to with my [trade] team. We've just known each other for a long time, and we have the same personalities and express ourselves by screaming with laughter, which not many people always understand," she laughed.
"It's nice to just feel that family atmosphere, as though you're still racing at junior level, so you never feel any expectation or pressure."
The Polish team could be happy with having made the top five in Saturday's race, too, thanks to Jasinska's ride.
"It's great – especially for Gorza. She's an amazing person, and has been trying to be up there for a long time, so I'm really pleased for her," Niewiadoma said. "She's such a powerful rider and a real fighter."
Now it's time for the Canyon-SRAM rider to relax and prepare for 2019.
"It's been a year when I've learned a lot – about myself, mostly – and I'm so stoked that it's all over," said Niewiadoma. "I just want to enjoy my holidays now."
Uttrup Ludwig left with 'mixed feelings' after road race
"Luckily, mistakes are something you learn from to become a better cyclist, but I think I need to sleep on it, go home and analyse the race, and to learn from the mistakes that I made today," the 23-year-old said, unwilling to divulge exactly what those mistakes were.
"I think it was cool to have a strong team around me," Uttrup Ludwig continued, referring to the six-woman Danish team that had worked for her during the 156.2km race. "We had Emma Norsgaard in the breakaway, Pernille Mathiesen getting water for me and Amalie Dideriksen putting me in the perfect position for the steep climb, and Annika Langvad in the final, so it was really cool that we rode well as a team.
"What went wrong? A lot of things. But I need to go home and think about it," Uttrup Ludwig repeated. "It's a shame when you end up with the feeling that you could have used your energy up in a different way, so I've got mixed feelings."
Uttrup Ludwig was part of a short-lived breakaway midway through the race, but admitted that perhaps she'd picked the move.
"It was actually something I'd been thinking about, having watched the men's under-23 race," the Danish time trial champion explained. "A lot of the riders in the top five had been in a breakway, and could do their own pace up the climbs, so I thought that was a good idea, and might give me a bit of an advantage.
"Maybe – or obviously – I should have chosen another breakaway, but that's also cycling, and that's one of the things I can learn from. I'm still young, and there are lots of world championships yet to come."
Women's 2018-2019 Transfers
You can find the full list of women's team transfers for the 2018-2019 seasons on our index here. Have information you'd like added to our list? Email firstname.lastname@example.org.