In a women's 1500m final that was always likely to set the pulses racing, Faith Kipyegon of Kenya backed up her Olympic success in Rio to take gold ahead of a stacked field.
Experienced championship performer Jennifer Simpson of the United States claimed silver, with Caster Semenya pipping home favourite Laura Muir on the line for the final medal.
Kipyegon holds off chasing pack to complete 1500m hat-trick
The 12 names which took to the start line read like a who's who of women's middle-distance running and the final lived up to the hype.
Muir was the woman to take the challenge of leading the race over the first lap, setting a fierce pace, before easing down over the next 500 metres as the race settled.
Pre-race favourite Sifan Hassan and Kipyegon moved towards the front of the race just before the bell, and then on the back straight they made their push for home.
Building a slight gap on the rest of the field, Muir and Simpson looked the most capable chasers, and once the race hit the home straight Hassan cracked.
Simpson and Muir both passed her, and were even closing down on Kipyegon, but the slow pace over the first half of the race had left a danger lurking. That danger came in the form of 800m Olympic champion Semenya, and with an incredibly strong finish she dipped past Muir on the line to push the Scot down into an agonising fourth-placed finish.
Kipyegon had done enough to take gold, adding to her Olympic and Commonwealth successes, with 2011 champion Simpson picking up her fourth major medal in this event ahead of 800 favourite Semenya.
Rojas pips Ibarguen to triple jump crown
In one the most highly anticipated head-to-heads of these championships, Venezuela's Yulimar Rojas claimed triple jump gold ahead of South American rival Caterine Ibarguen.
The duo have dominated the event between themselves this year, and on Monday evening it was Rojas who finish top of the podium thanks to her fifth round leap. That jump of 14.91 metres pushed her out past Ibarguen's third-round effort by all of two centimetres.
Colombia's Ibarguen wasn't going to let her crown slip easily though, and with the final jump of the competition she threw everything into it but the measurement left her four centimetres of snatching back the gold.
Rojas became Venezuela's first ever World Champion in the process, doubling their medal tally in London following Robeilys Peinado's bronze in Sunday's women's Pole Vault.