Connor Ronan eased St Mirren's relegation worries and added to Hibs' woes after scoring the only goal in a narrow 1-0 Premiership victory at Easter Road.
The on-loan Wolves midfielder pounced on a mistake from Jake Doyle-Hayes in the 62nd minute before firing a fierce drive beyond Kevin Dabrowski.
The victory moves Saints 11 points clear of bottom side Dundee and only within one of the top six.
Hibs were booed off by their fans at full-time after their winless league run stretched to five matches, which includes them failing to find the net in four of those games.
The home side had looked lively at the start of the second half following a poor first-half showing but were made to pay for failing to score when they were on top.
Hibernian manager Shaun Maloney continued to show faith in Dabrowski in goal following a man-of-the-match performance on his debut in the midweek draw with city rivals Hearts.
And the shot-stopper was the busier of the two goalkeepers in a first half that was edged by St Mirren.
Following a disjointed start to the game by both teams, the visitors had the first meaningful effort on goal in the 17th minute when Richard Tait angled a drive just past Dabrowski's far post from outside the box.
Jordan Jones was then presented with a chance from a similar range but the outcome was still the same.
St Mirren looked particularly lively on the counter and Jay Henderson forced a save from Dabrowski in the 22nd minute, with Rocky Bushiri clearing up the rebound.
In a rare opening at the other end, Kevin Nisbet and Christian Doidge combined to set Chris Mueller free in the box but the United States international was denied by a last-gasp Joe Shaughnessy challenge.
Hibs brought on Ewan Henderson for Doidge at half-time and the hosts looked far more threatening.
Henderson was denied by a brilliant Jack Alnwick save from a Nisbet lay-off before the former Celtic youngster shot narrowly wide.
The same two were denied again moments later but this time Henderson's shot was expertly pushed over the bar by the Saints goalkeeper.
The hosts' wastefulness in attack came back to haunt them when Ronan gave St Mirren the lead in the 62nd minute.
The midfielder pinched the ball off Doyle-Hayes just outside the box and drove forward before drilling a thunderous drive past Dabrowski from 18 yards.
Nisbet then came close to equalling moments later with a first-time drive from inside the area but Alnwick somehow managed to push the shot beyond the post.
Maloney rang the changes from the bench as he looked for inspiration but St Mirren held on.
