Marathon runners are often fiercely competitive people. And the London Marathon is one of the world's biggest stages.
That didn't stop Matthew Rees from stopping near the finish line to help David Wyeth across the finish line. BBC footage captured Wyeth staggering, barely able to walk. A marathon volunteer eventually came and helped the two of them finish the race.
Here's the heartwarming moment.
I thought, 'This is more important, getting him across the line is more important than shaving a few seconds off my time.'
Rees said he had just turned the final corner and prepared to sprint to the finish when he saw Wyeth.
Rees, who works at a bank, said he tried to cheer Wyeth on, but "he wasn't very coherent," and "every time he tried to move he would just fall again," The Sun reports.
Rees' selflessness quickly earned applause on social media.
The royal family attended the event, handing out water bottles to the runners.
Daniel Wanjiru, 24, of Kenya, won the men's race in 2:05:56. Mary Keitany, also of Kenya, won in 2:17:01, the second-fastest time in women's London Marathon history, the BBC reports.