South Shields saw their 21 match unbeaten record come to an end as they were hit by a late sucker punch against rivals North Shields on a record-breaking day at Mariners Park.
An incredible crowd of 2,651 packed in to watch the derby – smashing the ground attendance record by more than 800.
However, it was the visiting supporters who were celebrating in the end as, against the run of play, captain Kevin Hughes fired in the only goal of the game with six minutes left to snatch the three points.
The result left the Robins eight points clear of the Mariners at the top of Northern League Division One, although South Shields have two games in hand.
The teams entered the field to a rapturous reception, and the hosts immediately wrestled control of possession as the pattern for the game was set.
Clear-cut chances, though, were rare, with visiting goalkeeper Kyle Hayes called into action for the first time on 10 minutes when David Foley got in behind on the left before seeing a shot beaten away.
The Mariners probed patiently, but in wet and windy conditions, also tried their luck from distance on numerous occasions.
Robert Briggs let fly with one of those, and his effort was parried to Carl Finnigan, who, off-balance, could only turn the ball over.
Andrew Stephenson had a similar effort after stealing the ball high up the pitch and driving forward, with Hayes doing well to hold onto his shot.
A glorious chance was presented to the Mariners midway through the first half.
A sublime chip forward from Julio Arca was met by the chest of Stephenson, who was barged over by Curtis Coppen, and referee Helen Conley showed no hesitation in pointing to the spot.
Arca, who had a perfect conversion rate with penalties in his time with South Shields to that point, sent the spot-kick low to the goalkeeper’s left, but Hayes pushed the effort round the post.
Former Sunderland and Middlesbrough midfielder Arca almost made amends within three minutes as he twisted and turned outside the box before sending a low shot just wide.
Attacks from the Robins were rare, with the visitors seemingly content to let the Mariners have the bulk of possession in the hope of hitting them on the break at some point.
And that almost happened as they drove down the left before a teasing, low delivery across the area seemed destined to be turned in by Stuart Donnison at the back post, only for Anthony Callaghan to save the home side with a last-ditch interception.
Finnigan had a half-chance to put South Shields in front three minutes before the break, but he could only divert a header wide from a Foley left-wing cross.
Although the Mariners did have the majority of possession and looked much the more likely team to open the scoring, the Robins always looked solid and proved extremely difficult to break down.
The one time South Shields did break through the back line in the second half was in the 53rd minute, with Stephenson getting in behind on the left before pulling a ball across goal for Foley.
He looked certain to score, but a terrific block from Gary Ormston denied him, and when the ball broke towards Finnigan, visiting captain Kevin Hughes got there first to clear.
Chances were few and far between in the remainder of the half, with Arca having a low shot saved by Hayes before Briggs hammered an effort not far over from 20 yards.
North Shields had not forced home goalkeeper Liam Connell into any meaningful save, but with six minutes to go, they took their only opportunity of the half.
A corner from the left was half-cleared and then lifted back into the box, where two shots were blocked before the ball broke the way of Hughes, who took a touch and then rifled into the bottom corner to spark huge celebrations from the visitors.
The Robins had defended well throughout, and with the added boost of being a goal in front, it looked a tall order for the Mariners to force an equaliser in the remainder of the game.
They probed and tried to find a way through, but the visitors kept their concentration and, despite conceding most of the possession during the 90 minutes, took the three points back over the River Tyne.
The reverse fixture between the sides is in April, with many twists and turns in Northern League Division One almost certain to follow in the months in between.
For the Mariners, they have another midweek without a game before taking on Marske United in the FA Vase on Saturday at Mariners Park.
SOUTH SHIELDS: Connell, Danny Carson (Baxter 71), Callaghan, Arca (c), Morse (Ramsey 88), Shaw, David Carson, Briggs, Finnigan, Stephenson, Foley (Phillips 81).
WORDS: Daniel Prince. IMAGE: Peter Talbot.