American runner Abbey D'Agostino
ran more than a mile to complete her Olympic 5,000m heat despite tearing
her anterior cruciate knee ligament.
The American ran four laps with a torn ACL but will miss Friday's final because of the injury. D'Agostino managed a few steps after helping Hamblin to her feet before falling to the track, with the New Zealander returning the favour and helping her rival up.
The American hobbled over the finish line, with the two embracing before both runners were put through to the final by the track officials.
However, D'Agostino, who left the arena in a wheelchair, will miss the rest of the season.