Durham's Seconds played out a dramatic tie before losing the second T20 against Derbyshire at Belper.
With 11 needed from the Barry McCarthy's final over, the Irishman conceded nine from the first five balls & Derbyshire scampered a single from the final ball to settle a pulsating match.
Michael Richardson top-scored with 58 as Neil Killeen's men made 154/8, which a strong Derbyshire outfit matches for the loss of seven wickets.
He was well supported in a partnership of 61 for the third wicket with Jack Burnham, who hit three maximums in a knock of 33.
The hosts made a strong start through Ben Slater & Matt Critchley before Adam Hickey removed the latter & Josh Coughlin struck twice to remove Matt Henry & Slater.
An excellent 18th over by McCarthy, including the wickets of Luis Reece & Tom Taylor alongside the run out of Alex Hughes, swayed things back in Durham's favour before Ben Cotton departed with 12 needed from eight balls.
However, it went right down to the final delivery & the hosts did enough to salvage a tie.
In the second match, Derbyshire came out on top via the D/L method.
Slater's 75 in a partnership of 84 with Hughes ensured they got up to 154/4 from 18 overs.
In reply, Hickey top-scored with 36 while Scott Steel finished unbeaten on 35, with McCarthy adding 28 from 18 balls.
But mid-order wickets left Durham with too much to do towards the end.