Brighton Marathon runners almost went the extra mile, after race organisers revealed the course was too long.
Sunday's 26.2 mile event started at Preston Park in the city and finished near the Brighton Pier with more than 7,500 people taking part.
However, race organisers later said there had been a mistake with the course measurement that meant it was more than a third of a mile too long.
In a statement on Facebook, they said: "We would like to apologise to our marathon participants that the course today has measured 568m too long.
"We are wholly disappointed that this has affected our runners & hope that it hasn't marred the experience, at what has been a fantastic comeback event after 18 months."
In the men's event, Neil McClements overtook the then leader Ollie Garrod 200 metres before the finish line.
Mr McClements crossed the line first in two hours and 33 minutes.
Verity Hopkins was the fastest woman, with a finishing time of two hours and 52 minutes.
Mr Garrod, a 28-year-old accountant, admitted he was "frustrated" by the error, but added he understood the pressures involved in measuring the course.
He told The Telegraph: "Basically a cone up near Rottingdean was put too far up the hill and we kind of all knew as we went round - I looked at my watch and thought 'hang on, these mile-markers are suddenly half a mile out' and wondered how that happened at such a short distance."
Although some people expressed disappointment on social media at how the error had affected their timings, many made light of the situation.
One person wrote: "That explains the extra 40 minutes on my time...
"A great event regardless. AMAZING crowds and my thoughts go out to those who needed medical attention along the way, I hope everyone is ok."
Another added: "Does that mean you're gonna advertise it as an ultra from now on?"
The error comes four years after organisers of the Brighton Half Marathon revealed the course had been 146 metres (0.09 miles) short since 2015.