THOUSANDS of runners who completed three recent Greater Manchester marathons have been left feeling short-changed, after organisers admitted the course wasn't long enough.

The finishing line was found to have been put 415 yards too early for the races through Trafford in 2013, 2015 and 2015.

A measurement blunder meant runners didn't complete the full distance of 26 miles and 385 yards.

Around 24,000 results have been affected over the three years.

The error was spotted and corrected ahead of this year's race.

The error was announced by the Association of UK Course Measurers (AUKCM).

Marathon courses are measured using a bicycle with a specially fitted counter to track the distance by the turning of the wheels. It is believed a calibration error led to incorrect measurements being taken.

AUKCM secretary, Phil Holland, said: "AUKCM regret the error in measurement and the effect it has on runners’ times."

Race organiser, Xtra Mile Events, said: “Xtra Mile Events understand the anguish and huge disappointment this creates, and want to assure our runners that we share the upset and emotion from the AUKCM news regarding the race distance.”

"The 2016 Greater Manchester Marathon was not affected as it took place using a new course which is fully IAAF/AIMS certified."