Muir has endured a difficult year, quitting a training camp in South Africa and splitting with her coach Andy Young.
But arriving in Budapest, she said she was happy again and had her eyes on a medal to add to the silver at the Tokyo Olympics and bronze at last year’s Worlds in Eugene having previously been an also ran when it came to the outdoor major championships.
But the pace from Kipyegon proved too much for Muir, who fell back to sixth with 200m to go and maintained that position to the line
Mother-of-one Kipyegon, who had set three world records over three different distances in the course of just 50 days, was a class apart.
Ethiopia’s Diribe Welteji took silver with Sifan Hassan, who had fallen when within sight of gold in the 10,000m earlier in the championship and with her right elbow heavily bandaged, completed the podium. Ireland’s Ciara Mageean was agonisingly just outside the medals in fourth.
It meant a second night without a medal for the Great Britain team, whose count stands at a gold, silver and bronze.
Matt Hudson-Smith had left his last race towards the end of last month in London in a wheelchair – but insisted he was fit enough to take his place in the British squad for Budapest.
Despite the setback, he marked himself out as a serious medal contender for the 400m after producing a lifetime best to upstage former Olympic and world champion Kirani James in an impressive display in his semi-final.
A bronze medallist from last year’s Worlds, Hudson-Smith paced his run perfectly and eased up approaching the line but still clocked a PB of 44.26seconds. In the process, it also beat a European record for the event, which had stood for 36 years.
Afterwards, he played down the importance of his time. He said: “I will be happy when I get that medal. As for today, that is just job done. I just need to get that medal now. I am really happy to have made it and it is all about getting that medal on Thursday.”
All three British men are through to the final of the 800m after qualifying from their heats.
Max Burgin and Ben Pattison were both runners-up in their heats while Daniel Rowden described himself as “fortunate to get through” having had to jostle for position to get one of the automatic qualifying spots.
For Burgin, for whom injury struck at both last year’s Worlds and the Commonwealth Games, described his return to a major championship as “a long time coming”.
He said: “It has been frustrating missing all these major championships over the last couple of years, so it feels great that I have finally made it. I made it to the start line and got into the semis so it is already an improvement on last year. “
Jessie Knight, though, missed out on one of the fastest losers spots for a place in the final of the 400m hurdles.