The fireworks came in a free-scoring second half and despite conceding the bulk of possession the battling Dragons marched to victory and closed the gap at the top of the table.
It was a triumphant first Dragons appearance of the season for outside half Craig Warlow, who put a frustrating few months behind him with a match-winning 18-point display.
The out of sorts Ospreys looked to young Matthew Jones for inspiration but not even his 19 points could rescue the sad visitors.
Both sides were deprived of eight players apiece due to international call-ups and injury in what was a real test of the strength in depth of the two leading Welsh regions.
Jones fired the Ospreys into the lead after just two minutes, with Warlow replying for the Dragons a couple of minutes later after a storming Richard Bryan run has ripped open the visitors’ defence.
The league leaders created a chance for Stephan Terblanche and it took a perfectly timed ankle tap by Jamie Ringer to deny the South African flyer.
But the Dragons raised the tempo to go in front for the first time courtesy of a second Warlow penalty, before Jones responded in kind after 18 minutes to restore the status quo.
The kicking duo continued as Jones completed his penalty hat-trick to nudge the Ospreys back in front.
A brilliant break by Warlow, who stepped inside his rival Jones, dealt a crushing blow to the Ospreys hopes, Sione Tuipulotu providing the link for Kevin Morgan to race in unopposed for a superb score.
The conversion by Warlow opened a four point gap, which Jones trimmed to a single point with his fourth penalty. But Warlow missed an easy shot at goal and the Dragons had to settle for a 13-12 lead at the interval as the Ospreys reflected on a series of missed opportunities.
A combination of tight home defence and ponderous play at the breakdown meant that the Ospreys’ possession counted for nothing and they suffered another blow as the Dragons plundered 13 points in a devastating nine minute spell.
Smart thinking by Tuipulotu led to Morgan crossing for his second try with Warlow converting and adding a drop goal and penalty to put the Gwent region 26-12 ahead moving into the final quarter.
The hapless Ospreys continued to splutter through, spilling passes which blighted their attempts to convert a plentiful supply of possession into points.
Instead, they relied on Jones, with a fifth penalty to keep their fading hopes flickering. Then with four minutes left replacement Jason Spice broke away to score an opportunist try, which Jones converted, after Richard Mustoe had made the thrust.
But the Dragons clinched victory with a barnstorming late try by replacement prop Rhys Thomas, converted by man-of-the-match Warlow.
The Ospreys salvaged a bonus point through a last gasp touchdown by Dave Tuieti, converted by Jones.
