Matthew Rees, of Swansea Harriers Athletics Club, was near the finish line of the 26.2-mile race on Sunday when he was seen assisting David Wyeth, of Chorlton Runners.
Video of the race shows Rees grabbing Wyeth, who was struggling to finish the race. The duo walked to the finish line, with Rees cheering and showing Wyeth how close they were to the end.

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