Rushden & Diamonds shocked Tranmere Rovers with a 2-1 victory at Prenton Park.
The Merseysiders were hoping to equal a 30-year club record of 18 league games without defeat, but paid for a poor first-half display.
The visitors produced all the good football in the opening 45 minutes, but then it became a real back-to-the-wall task as they held on defiantly in the face of a grandstand home finale.
Rodney Jack fired Rushden ahead in the sixth minute with a super strike from the edge of the box following a cross by Marcus Bignot.
David Bell doubled the margin in the 33rd minute with a fine lob over the keeper after an interchange of passing with Paul Hall.
Tranmere created little early on, but Gary Jones put them back in contention when heading home a Sean Connelly centre in the 69th minute.
Rushden then had to show all their resilience in defence as it became one-way traffic towards their goal.
Keeper Bill Turley produced some terrific saves, none better than in injury time when he denied Jones and Ian Sharps.
He also had a little luck on his side in the 90th minute, when a Jones shot deflected off Iain Hume on to the bar.
Admitted, Rushden boss Brian Talbot: "It was a draining experience, especially when Tranmere threw everything at us bar the kitchen sink late on.
"The players have taken the club to new heights today with a first ever away win in Division Two, but we must not get carried away even though we spoiled Tranmere's party." Tranmere boss Ray Mathias said: "We paid for a terrible first-half performance. We thought we could easily win the game and did not give the opposition enough respect.
"But all credit to the players for their second-half fightback when the Rushden keeper made some fantastic saves."