Ciara Mageean recorded a personal best time at the Irish Milers' Club meeting at the Mary Peters Track in Belfast.
The Portaferry runner set a time of 2:02.31, bettering her previous best of 2:03.07 from two years ago.
Mageean was competing in a mixed sex race and while the time will not count for record purposes it shows that the 'A' standard for next year's Olympics, 1:59.80, is perhaps within her grasp.
Mageean had crashed to a surprise defeat at Santry the previous week.
Her time ranks her second fastest in Europe and seventh on the world Junior lists.
It is also the fastest time by a Northern Ireland athlete in 13 years and is only half a second slower than Amanda Crowe's NI record of 2:01.83, achieved at the 1998 Commonwealth Games.
In last week's Irish Championships Mageean misjudged her first lap at 57.5 seconds and as a result lost the race in the final few strides.