South Shields were beaten 1-0 by Durham United as their involvement in this season's Durham County FA Frank Pattison Challenge Cup came to an end at the first round stage.
Andy Inness and Elliott Dickman led a team of the club's 16-19 Academy players at Maiden Castle, and the young Mariners performed well against the Wearside League outfit.
They probed relentlessly for an equaliser in the second half but were unable to find a way through as they fell to a narrow defeat.
There were opportunities at both ends in the early stages.
George McArthur was denied by a fine save on seven minutes and Dan Savage also got on the end of an opening, but fired wide.
Bryan Taylor was a lively presence on the left flank and got forward well from his left-back position. He was played in down the side of the area just before the half-hour mark and his well-struck effort flew wide.
Durham scored what would prove to be the only goal eight minutes before half-time when Alex Costa capitalised on a defensive error to convert from close range.
There were plenty of bright passages of play in the second half from the Mariners, and they almost equalised with a Savage shot which home goalkeeper Reuben Bull did brilliantly to keep out.
The hosts breathed a sigh of relief with 20 minutes left when an attempted clearance from a Durham defender flew inches past the post.
Shields increased the pressure in the closing stages and went close to a leveller three times.
Substitute Nathan Kidd fired narrowly wide from a tight angle and was then denied by an excellent save from Bull after being played in on goal.
There was still time for one more agonising moment as Savage's free-kick from 20 yards crashed against the crossbar.
It ultimately proved to be one of those nights for the young Mariners.
South Shields: Walker, Bell, Taylor, Duffy, Hegarty, Davison, Neary (c), Henry, McArthur, McGowan, Savage. Subs: Kidd, Watts, Telfer, Beresford, Fletcher.
Image: Ian Kelsey.