South Shields joint-manager Graham Fenton admitted his side dropped well below their standards following their late FA Cup exit to Stockport County.
The Mariners were minutes away from a replay at Edgeley Park however substitute Nyal Bell broke the hosts’ hearts when he popped up in injury time for the National League North team.
Carl Finnigan handed Shields the advantage on the half-hour but seven minutes later, Sam Walker capitalised on Liam Connell's mistake to level.
Fenton stated he didn’t care that the Hatters are one league above, believing South Shields are the better team but were ultimately nowhere near their best on Saturday.
However, he did concede that the Mariners deserved to be knocked out the FA Cup at the second round qualifying stage.
The former Blackburn Rovers forward said: “It was a good occasion – a really good occasion. We love having days like this at Mariners Park but we’re really disappointed.
“We weren’t anywhere near our best. They turned it into a scrappy game and we almost went toe-to-toe with them – they’re better at scrappy games than we are.
“We didn’t show our identity anywhere near well enough. We didn’t shift them about anywhere near well enough.
“We didn’t show enough bravery in possession to give each other enough angles to shift them around and get them tired like we usually do teams.
“I think, possibly, the occasion got to a few people but I don’t care if they’re a league higher or not, we should not be getting beat off teams like that given the way they play.
“I said to the lads, I don’t care where they’re from, they are not as good as us as a team. They beat us because we weren’t anywhere near our best – it’s that simple.”
A neat flick by Gavin Cogdon – who limped off soon after the opener – fed in Blair Adams on the left-hand side of the penalty area and his delivery across the six-yard box was tapped home by Finnigan.
In the end, it was two set pieces that unlocked the Mariners' defence with Walker and Bell – in the 92nd minute – completing a devastating turnaround.
"Ultimately, they’ve scored off two set pieces – so that’s what they are all about,” said Fenton.
“We were slightly better - we weren’t great first-half but you can’t give goals away like that, not at the end of the first-half to give them a little bit of encouragement.
“The two front lads were decent for them, they put their bodies in, they buy fouls, they play for set pieces, they’re good on set pieces - they’ve scored from two and that’s why we’re out the FA Cup.
“It’s great to be involved in things like this but not when you get beat and especially off teams that aren’t as good as you when we play to our best.
“We have not shown enough of ourselves today and we deserve to be out the FA Cup.”