For a few thrilling seconds halfway down the home straight Adam Gemili had a 200m world championships medal locked and loaded. All the 25-year-old needed to do was carry his form through the final 60 metres, usually the best of his race. And then, savagely, lady luck intervened to scupper his dreams yet again.

A wobble became a stumble. And a stumble turned a silver or bronze into yet another fourth place finish. Understandably, having seen a first global medal slip through his fingers yet again, the tears started to flow - and so began another brutally honest postmortem.

“I am gutted,” said Gemili. “I had it. I lost my balance. I had nothing left at the end. All my form went out of the window. I ran like an amateur, I cannot believe it, I came so close, this was such a good chance. My body feels good, I ran well through the heats. I let it go.”

His time of 20.03sec was a season’s best. But it was painfully short of the American Noah Lyles, who celebrated his first world title after coming home in a modest 19.83 sec. Short of the Canadian Andre De Grasse, who took silver in 19.95. And short of the Ecuadorian Alex Quinonez, who came home in 19.98.

“I am sorry, I feel like I have let down so many people,” admitted Gemili. “So many people sent me messages. The team know I have been plagued with injuries.”

Gemili has had this feeling before. At the 2016 Rio Olympics he finished fourth in the 200m final, three thousands of a second away from bronze.

“It’s the same, if not worse than that feeling after Rio because of the story behind it, where I’ve come from after injuries and being written off completely.

“To not break 20 seconds is so disappointing and heartbreaking. I had the medal and it slipped out of my hands. Fourth is the same as eighth, the same as 16th. Unless you’re on the podium, who cares?”

Still, at least Gemili ended on an upbeat note. “It hasn’t happened today, but it has relit something inside me,” he said. “If I go to Tokyo it’s winnable.”

Noah Lyles celebrates after crossing the line. Photograph: Christian Petersen/Getty Images

It means that Britain still only has one medal after five days of competition. However Dina Asher-Smith is a penalty kick away from gold in the 200m after yet another potential rival, Elaine Thompson, was ruled out through injury. It means that only four of the top 10 in the world will be in Wednesday’s final – with Asher-Smith fastest of all.

“Dina is going to win,” predicted Gemili. “This is the best opportunity for a female sprinter to win a medal. She’s miles apart from everyone. It’s not about if she’s going to win it, it’s about how fast she can go. I’m hoping she can do something really special.”

Elsewhere there was an easy victory in the 800m for the Nike Oregon Project athlete Donavan Brazier in a US record 1:42.34, ahead of the Bosnian Amel Tuka and the Kenyan Ferguson Cheruiyot Rotich.

When Brazier was asked what he knew about Alberto Salazar’s doping ban, he surprised his audience by telling them: “I didn’t actually know the investigation was going on. And he’s not my coach - I’m coached by Pete Julian.”

When some put it to him that what had happened might have changed his opinion of Salazar he shook his head. “No. The only contact I’ve had with Alberto has been pleasant. I like Alberto. He’s a cool guy.”

And when asked if he would stay with the Oregon Project, he added: “Yeah, if Pete takes control.”

Meanwhile a thrilling men’s pole vault competition was won by the American Sam Kendricks, who cleared 5.97m to defeat the Swedish teen sensation Mundo Duplantis to gold.