A seven-goal thriller at the Millerntor Stadium seen Paderborn just about get the better of a dogged St. Pauli side.
A brace from Niklas Helenius set them on their way to victory, with Thomas Bertels and Florian Hartherz also getting on the scoresheet.
The hosts put together a late comeback, but Lasse Sobiech's penalty and Waldemar Sobota and Fabrice Picault's goals proved in vain.
Both teams made few changes to their line-ups from the previous games. Fabrice Picault (benched) and Lennart Thy (injured) were replaced by Waldemar Sobota and Kyoung-Rok Choi after St. Pauli's defeat to 1. FC Heidenheim, while Paderborn stuck with the same side that drew with Greuther Fürth.
Helenius produces a moment of magic
The opening 10 minutes were anything but tight and tense, as both sides went in search of an early opener. The visitors went close with a Süleyman Koc free-kick, and the midfielder also felt he should have earned a penalty when Enis Alushi clattered into him. At the other end, Philipp Ziereis blazed over from the edge of the area while Jeremy Dudziak failed to make clean contact on a bouncing ball inside the six-yard area.
But within the opening exchanges, there was a goal and a quite breath-taking one at that. Niklas Helenius collected a throw-in from Khaled Narey and proceeded to flick the ball over the head of two defenders inside the box before sending a powerful volley past in off the bar; a super strike that sparked the home fans into a chorus of chants.
The increase in noise seemed to up the intensity of the hosts, as Daniel Heuer Fernandes was forced to shovel a strong shot onto the base of the post before Alushi rifled an effort into the side-netting. The confidence had returned, though the all important goal to go with it was missing.
Despite that period of pressure, St. Pauli would fall further behind. A quite superb team goal from Paderborn saw them extend their lead, Florian Hartherz finished with aplomb. Some snappy passing saw Helenius free up Kevin Stöger down the left, and he picked out Hartherz in the middle to coolly slot past the advancing Robin Himmelmann. The home stopper made a vital save in the minutes that followed, producing a stunning stop to keep out Hauke Wahl's header.
St Pauli threw in several more crosses towards the break, but the lack of Thy in the box meant that they were almost always headed clear. Moritz Stoppelkamp had a further chance to inflict more misery on the hosts, only to see his effort fly over; in the end, Ewald Lienen's side could count themselves lucky to be down by just two.
Superb second half sees Paderborn scrape through
The second half brought drama from the start, as St. Pauli put Paderborn under massive pressure from the restart. That immediately paid dividends, as Tim Sebastian hauled down Lasse Sobiech in the area. Wolfgang Stark had no choice but to point to the spot, and Sobiech quickly dusted himself down before finding the top corner.
That joy would be short-lived, however, as Paderborn stole a third on a counter-attack. The visitors were continually fouling the opposition on the edge of their area, but a quick break saw Stoppelkamp racing down the right with Helenius free in the middle. The Dane shot first-time and brought a fine save from Himmelmann, but the ball trickled on over the line after Ziereis was unable to hook it clear.
St. Pauli, undeterred by the position they were in, still came forward in a bid to get back into the game. Substitute Sebastian Meier picked out Waldemar Sobota to seemingly reduce the deficit to one but he was flagged for offside, although it was very, very close.
Paderborn then struck the blow that assured them of three points. A driving run by the energetic Hartherz had the hosts on the back foot, and he picked out Thomas Bertels with a clever pass to go through on goal. The wing-back took his shot early, catching Himmelmann off-guard to add some gloss to the score-line.
Any chances of an easy end to the game were quickly blown out of the water, however, as Sobota finally got his goal. Some good play by Picault created the chance and he picked out the Pole at the back post, only to see his header come back off the post. Heuer Fernandes made a super stop from the rebound, but was powerless to prevent Sobota's third attempt from going in.
The impossible comeback seemed alive when Picault rose highest to head home Marc Rzatkowski's free-kick in the 93rd minute, only to hear Stark blow for full-time soon after. It was an incredible game from start to finish and a draw would have been a fair result, but this win has done Paderborn the world of good in the battle to beat the drop and they now sit just a point behind 1860 Munich in 15th. As for the hosts, their promotion dreams seem all but ove; St. Pauli fell eight points behind the top three with the result.