Wayde van Niekerk broke down after Ramil Guliyev denied him a IAAF World Championships sprint double, while Christian Taylor and Kori Carter took gold on another fruitful night for the United States.
Van Niekerk has had to listen to talk of conspiracy theories since winning the 400-metre title on Tuesday in the absence of Isaac Makwala, who was prevented from going for gold in his preferred event.
Two days after Makwala was denied entry to London Stadium after he was placed under quarantine following a norovirus outbreak, the Botswana sprinter finished sixth in a 200m final which was won by Guliyev on Thursday.
Van Niekerk had to settle for silver in an emotional night on the track, failing to achieve a double which only Michael Johnson claimed back in 1995 as Guliyev won Turkey's first ever World Championships gold.
Taylor won a record third triple jump title at the expense of compatriot Will Claye, while Carter and Dalilah Muhammad gave the USA another one-two in the 400m hurdles.
The USA are well clear in the medals table with 19 in total, six of which have been gold.
-- IAAF World Champs (@IAAFWorldChamps) August 10, 2017
VAN NIEKERK HITS BACK AFTER 200M SILVER
Much of the talk ahead of the 200m final centred around whether Van Niekerk and Makwala could claim the title, but it was Guliyev who was crowned champion.
The Azerbaijan-born sprinter dipped across the line to snatch it in 20.09 seconds, edging out Van Niekerk and leaving Jereem Richards to settle for bronze. Makwala endured more disappointment after so many questions had been asked over why he could not run in the 400m.
While Guliyev celebrated making history for Turkey, a dramatic week caught up with Van Niekerk, who needed time to compose himself before conducting a post-race interview.
The 400m world-record holder told the BBC: "I work just as hard as every other competitor I compete against, I show everybody else respect and I think I didn't get the respect I deserved after the 400 metres.
"I'm glad that I came through today and put on a show, I believe this is only the beginning. I am going to put in so much work and show my dominance."
TREBLE FOR TRIPLE JUMP KING TAYLOR
Taylor was in a class of his own once again in the triple jump, leaping 17.68m to add another gold to his enviable collection.
Claye took silver, after also finishing second behind his compatriot at the Rio Olympic Games last year, while Nelson Evora filled the podium for Portugal.
Taylor could not break Jonathan Edwards' long-standing world record, but still has that target in his sights after his latest success.
"I have this watch from my sponsor with 18.30 on it. I will try to fight, I will get this number. The record is still on. I am still motivated to break that record." he said.
"My motivation is to be the best athlete. This was not the night, I am a little disappointed. But the season is not yet over."
CARTER 'ON TOP OF THE WORLD' AFTER HURDLES GLORY
Zuzana Hejnova was aiming to become the first three-time world champion in the women's 400m hurdles, while Olympic champion Muhammad was well fancied to repeat her success in Rio.
It was Carter who came to the fore, though, charging away in the outside lane to win in 53.07secs.
Ristananna Tracey took bronze for Jamaica behind Muhammad, with Hejnova finishing out of the medals in fourth.
Carter said: "I am on top of the world right now. What a blessing to be world champion. This is just an incredible feeling like I have never experienced."
SCHIPPERS AND MILLER-UIBO COAST THROUGH
Defending champion Dafne Schippers and Shaunae Miller-Uibo recorded the same time to win their 200m semi-finals.
Schippers eased to victory with an imperious run, looking very much capable of retaining her title on Friday as she clocked 22.49secs.
With no Tori Bowie and Elaine Thompson in the event, Miller-Uibo matched Schippers' time to win the second semi-final a day after missing out on a 400m medal, when she looked set for gold but slipped back three places in a dramatic end to the final.
Marie-Josee Ta Lou, the 100m silver medallist, won the other semi-final.