Never-say-die Southport scored three times in the final 23 minutes to come back and win at 10-man Gateshead.
Prolific striker Jon Shaw put the hosts ahead with a left-foot strike before Yemi Odubade tapped in Chris Carruthers' cross to double the lead.
Shaun Whalley gave Southport a lifeline when he squeezed home from 12 yards.
Whalley then fired a 25-yarder into the top corner and, with Josh Gillies sent off for foul and abusive language, Vinny Mukendi hit a last-minute winner.
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Gateshead manager Ian Bogie told BBC Newcastle:
"I had a right go at them just before they went back out at half-time. I said at 2-0 the game is at a dangerous stage because if they get a goal then the momentum is with them.
"They're very direct, and for how good we were in the first half, we were twice as bad in the second.
"There's no excuse. Defensively it's not about tactics or shape or organisation; it's about rolling your sleeves up and we were found wanting."