Kamga came into the women's discus final having set the best mark in the qualification round, while Caisa-Marie Lindfors was also looking to compete for medals having qualified in 10th place.
Beginning her final with a 63.66m effort, Kamga improved to 64.39m with her next attempt to get into medal contention, but failing to improve on that in round three kept her in bronze medal position at the halfway stage.
The 27-year-old, who finished fourth in the world championships a year ago, then threw 64.61m in round four, her best of the night but still a few centimetres short of her best in qualifying. A foul with her penultimate attempt meant no improvement, though she was clinging on to third place.
With her final throw, the bronze was already secured, but she needed to surpass 67.67m to have any chance of taking gold, but she was unable to increase her best again.
Kamga stepped out of the circle all smiles, knowing that she had her first major championship medal after coming so close in Tokyo and at the Paris Olympics, where she finished fifth. It is the first major medal for Sweden in women's discus since the 1928 Olympics.
Gold went to Jorinde van Klinken of the Netherlands with that 67.67m throw, and silver to Germany's Shanice Craft, whose best effort travelled 65.72m.
Lindfors put in a very respectable performance in the final, adding nearly 3m to her qualification mark to finish seventh with a best throw of 62.39m.
One and done for Mondo
Passing the opening two heights, Duplantis sailed over 5.60m at the first attempt when he entered the competition, and with only 11 others able to match that height, that was all the Swedish superstar needed to qualify for the final, which takes place on the final evening of competition on Sunday 16th.
Mondo looked fresh and comfortable following the injury he suffered in London earlier this season, but with only one attempt some 80cm shorter than his latest world record, only on Sunday will fans see if he is back to his best.
His closest challenger in recent years, Emmanouil Karalis of Greece, was also "one and done" at the 5.60m height.
Duplantis' compatriot William Asker will not be joining him in the final. The 22-year-old cleared 5.45m but only at the second attempt, a miss that saw him miss out on one of the final three spots up for grabs.
Edlund fourth in battle for minor 400m hurdles medals
In the evening session, Oskar Edlund was aiming to replicate the national record of 47.81 he set to finish quickest in the semi-finals of the 400m hurdles, as he competed for the medals in the final. From lane eight, Edlund made a strong start but it was clear the field could not contend with world record holder Karsten Warholm, who opened a healthy lead.
The Swede was then passed by Germany's Emil Agyekum as they entered the home straight, and though Edlund did just enough to hold off the other German, Owe Fischer-Breiholz, he was unable to stop Turkey's Ismail Nezir passing him on the inside and taking bronze.
It was a tough fourth place to take for the 23-year-old, who crossed the line in 48.36, as Norway's Warholm broke his own championship record, clocking 46.63.
Confident start from Pihlstrom
Samuel Pihlstrom took control of his 1500m heat, getting himself to the front with just over 300m gone and controlling the increasing tempo. With 200m to go, he was passed by Great Britain's Jake Wightman and Germany's Robert Farken, but the Swede still had enough to hold off further challengers in the home straight to finish third in 3:41.84.
That was more than enough for him to qualify for the final, which takes place in the evening session on 15th August.
Heptathletes struggling for consistency
Lovisa Karlsson began two days of events in the heptathlon with one of her strongest events, the 100m hurdles. In the heat for faster athletes, she was second at the halfway mark before being pipped on the line to finish fourth in 13.03, which also put her fourth overall. Down in 19th after the hurdles was Erika Warff, who ran 13.83 in the opening event. Next up was the high jump, in which Warff registered 1.74m, 3cm higher than Karlsson, but with the best jumpers clearing 1.86m, Karlsson was knocked down to 11th overall on 1987 points, while Warff climbed two places to 17th on 1906 points.
The heptathletes returned in the evening for the shot put, where Warff placed 11th in the group with stronger throwers, posting a best of 13.92m. That was enough for 12th overall, five places higher than Karlsson, whose 13.25m score put her fifth in the second group. That saw Karlsson drop another place overall, as Warff again crept up a place on the leaderboard.
The final event of day one was the 200m, which Warff ran in 24.85 to finish fifth in the opening heat. Karlsson was among stronger runners in heat two, clocking a faster time of 24.30, which saw her cross the line in sixth.
Those times meant Karlsson is in 14th place overnight on 3683 points, while Warff shas dropped to 20th on 3596 points, though only 14 points separate her and Adela Tkacova in 17th.
Meanwhile, there will be no women's javelin final for Beatrice Lantz, whose furthest throw of 51.06m saw her finish 29th in the 30-athlete field.
