Marathon runners who exhausted themselves in the Edmonton Marathon in the hope of qualifying for the marquee Boston Marathon may still have a shot.

The Edmonton Marathon says more than 10,000 people registered for its race Sunday, which was later found to be two-thirds of a kilometre longer than necessary.

Organizers initially dismissed complaints before remeasuring and concluding there was an error.

The race route was an extra 674.7 metres beyond the usual length (42.2 kilometres for marathon runners and 21.1 kilometres for those in the half marathon).

The issue was a detour to accommodate construction that wasn’t properly offset in the rest of the race.

That extra distance has introduced uncertainty for people who were hoping to use their marathon and half-marathon times to qualify for other prestigious races, such as the Boston Marathon.

A spokesperson for the non-profit Boston Athletic Association, which organizes the Boston Marathon, says in an email the marathon would not accept adjusted qualifying times.

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But the association also confirms that if an athlete ran farther than the required length, but still met a qualifying time for the marathon, they would still make the cut.

Edmonton Marathon director Tom Keogh says the event is communicating with its partners, including the Boston Athletics Association, to see how this year’s results can be recognized.

The Boston Marathon is scheduled for April 19 of next year with registration set to begin this September.