The organisers of the Great Scottish Run half-marathon have confirmed the 2016 course was 149.7m short of the stipulated 13.1 miles.
There was controversy following the event in Glasgow after some competitors questioned the length of the course.
The Great Run Company, which organised the race, confirmed the error in a statement today.
The failure means the Scottish half-marathon record set on the course by Callum Hawkins is now invalid.
“The miscalculation was down to human error and caused by two factors,” the company said in a statement.
“A small section of the prescribed route was not followed correctly in Bellahouston Park which accounted for 50m of the shortfall.
“The remainder of the shortfall was a result of the difference between measuring on closed roads compared to a measure on unclosed roads.
“Naturally we are extremely disappointed these errors have been made and have apolgised to Callum.
“We have also apologised to Betsy Saina, winner of the eltie women’s race.”