Watch: London Marathon runner carries struggling competitor to the finish line

Instead of shaving a few seconds from his personal finish, one runner carried a struggling competitor to the finish.

The closing miles of a marathon can be absolute bedlam. There's joy from those completing their first 26.2 mile race or clocking a personal best. There's tears knowing all the hard work from training paid off. There can also also dark moments like when your legs turn to Jello-O.

Matthew Rees saw someone going through the hurt locker and put the tired runner's arm around his neck before carrying him to the finish line.

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"I took the final corner thinking 'right, it's nearly done, time to sprint', and I saw this guy and his legs just crumbled below him," Rees told the Associated Press. "I saw him try to stand up again and his legs just went down again, and I thought, 'This is more important, getting him across the line is more important than shaving a few seconds off my time."

Sometimes you get by with a little help from your friends and other times a random stranger can be a hero.