Gladys Ganiel O'Neill of North Belfast Harriers failed in a brave attempt to get the Olympics 'A' qualifying standard in Sunday's Houston Marathon.
Ganiel O'Neill clocked a personal best time as she finished seventh in two hours, 40 minutes and 56 seconds.
She was eligible for the United States trials on the same day but opted for the Houston run instead after getting Irish citizenship.
Ava Hutchinson from Dublin did get the qualifying time for the London games
She clocked 2:35.33 to finish fourth in Houston, well inside the 2:37.00 cut-off mark.
Hutchinson was on track throughout the race, running consistent splits, unlike the Dublin Marathon in October when she was on track for the qualification time but faded in the final stages.
The Irish half marathon champion joins her Dundrum South Dublin clubmate Linda Byrne who had already achieved the standard.
Meanwhile European Cross Country champion Fionnuala Britton finished eighth in a race Sevilla, Spain.
Britton clocked 26.54 in an event dominated by African athletes and won by Linet Masi of Kenya in 25.42.