Guinea-Bissau's Braima Dabo produced a heart-warming display of sportsmanship as he helped an exhausted Jonathan Busby of Aruba across the line in the 5,000 metres at the World Championships in Doha.
Busby finished in Dabo's arms to huge cheers at the Khalifa International Stadium on Friday before collapsing to the track.
The runner needed medical attention after finishing the race - thanks to the help of Dabo in the final 300m - and was eventually taken away in a wheelchair.
Dabo sacrificed his own race but still ran a personal best of 18 minutes 10.87 seconds, although Busby was disqualified.
The race, in which Great Britain's Andrew Butchart finished seventh to scrape into the final, was won by Ethiopia's Selemon Barega in a time of 13 minutes 24.69 seconds.
World Championships round-up
Great Britain's Zharnel Hughes powered into the 100 metres semi-finals at the World Championships as Christian Coleman sent out a gold medal warning.
European champion Hughes won his heat in 10.08 seconds to comfortably go through on the opening day in Doha on Friday.
Coleman was the only man to go under 10 seconds as the American clocked 9.98secs in the final heat to underline his status as favourite.
They were joined in Saturday's semis by Adam Gemili, who came third in his heat, while defending champion Justin Gatlin, Andre De Grasse and Yohan Blake all eased through.
Hughes is a medal contender at the Khalifa International Stadium and could land Great Britain's 100th World Championship medal in Saturday's final.
He said: "I'm happy I got through, that's the main aim and that's what I came here to do - get through the rounds and on to the semi-finals. I'm feeling well. As long as I get it together I know I'll be fine.
"I know the start wasn't that amazing. I'll work on it. I have to find my setting on that block because it's a bit different from what I'm using. Once I find it I'll be fine."
GB team-mate Ojie Edoburun ran 10.23s in the first heat, coming fifth, but qualified as the final fastest loser.
It was a low-key opening to the championships, with the stadium barely half full and a top tier completely closed.
The official attendance was confirmed by the IAAF as 11,804 ticket-holders, plus 1,484 guests.
Shelayna Oskan-Clarke, the first British athlete to compete in Doha, reached Saturday's 800m semi-finals by finishing second in her heat.
She ran 2:02.09 behind American Raevyn Rogers and was joined in the next round by GB team-mate Alex Bell.
But Lynsey Sharp, considered a medal contender with defending champion Caster Semenya missing, surprisingly crashed out after coming fourth in her heat.
Holly Bradshaw reached the pole vault final with a first-time clearance of 4.60m, but Morgan Lake failed to progress in high jump qualification.
Andy Butchart squeezed into the 5,000m final after Norway's 19-year-old European champion Jakob Ingebrigtsen - one of the favourites for a medal - was disqualified for stepping off the track, with the Scot having initially missed out on a spot by one place.
Chris McAlister also reached the 400m hurdles semi-final after coming fourth in his heat.