Match ends, Dumbarton 3, Hibernian 2.
Dumbarton hung on to beat Hibernian and strike the second blow in the space of three days to the Leith side's Championship title chances.
The Sons were two ahead at half-time through Kevin Cawley's strike from distance and Christian Nade's header.
That lead became three when Darren Barr headed in from a corner.
The non-stop Liam Henderson curled in a beauty before Farid El Alagui drove in another, but Hibs failed to reap an equaliser from sustained late pressure.
With Rangers winning and the gap now at 11 points between the Ibrox side and Hibs - who lost 3-0 at home to Morton on Wednesday - with 10 league games to go, it would seem a huge slip-up would be required for Mark Warburton's side not to end up champions.
Alan Stubbs said after the Morton defeat it was important to show it was just "a blip", and Hibs appeared calm and composed as their much-changed starting XI got to grips with Dumbarton.
A passage of crisp passing started by Henderson was almost finished delightfully by the same player within the opening five minutes, meeting Niklas Gunnarsson's cross with his left foot and cushioning a lovely volley from 12 yards off the junction of post and crossbar.
Former Hearts striker Nade was enjoying his remit of pestering the Hibs defence and Paul Hanlon felt the full force of the Frenchman when he ended one of his runs.
But despite Stubbs' men apparent comfort, Dumbarton struck first through Cawley, finishing superbly into the bottom-left corner from 20 yards.
Danny Carmichael and Jason Cummings both sent efforts narrowly wide of goal - misses that proved costly when Dumbarton extended their lead three minutes before half-time through Nade's first ever goal for the club.
The 31-year-old rose to glance Mark Docherty's delivery past the onrushing Mark Oxley.
More jubilation followed straight after the break for the Sons when another former Jambo in the shape of Barr met Calum Waters' corner at the near post to bullet another header in off Oxley.
Nade was withdrawn and goaded the Hibs fans with a 5-1 gesture in reference to their Scottish Cup final defeat to Hearts in 2012.
But almost immediately Henderson answered with a mazy run and wonderful finish into the top corner to reduce the deficit.
Henderson's engine was admirable and the man on loan from Celtic was soon instrumental in a second Hibs goal.
He had a shot cleared off the line by Docherty before taking the corner that resulted in substitute El Alagui driving the ball into the net following a scramble.
The Easter Road side piled on the pressure and amounted 16 corners as they searched for an equaliser but Dumbarton showed great resolve to secure crucial points as they try to avoid being embroiled in a relegation fight.
- 5BuchananBooked at 47mins
- 23WalshSubstituted forTaggartat 67'minutes
- 7CawleySubstituted forKirkpatrickat 79'minutes
- 27NadeSubstituted forFlemingat 62'minutes
- 4HanlonSubstituted forFontaineat 63'minutes
- 6BartleySubstituted forBoyleat 57'minutes
- 3HendersonBooked at 90mins
- 19KeatingsSubstituted forEl Alaguiat 57'minutes
- 9El Alagui
- Barry Cook
- Shots on Target
Second Half ends, Dumbarton 3, Hibernian 2.
Liam Henderson (Hibernian) is shown the yellow card.
Jordan Kirkpatrick (Dumbarton) wins a free kick in the defensive half.
Foul by John McGinn (Hibernian).
Attempt blocked. John McGinn (Hibernian) right footed shot from the centre of the box is blocked.
Attempt missed. Liam Henderson (Hibernian) right footed shot from outside the box is just a bit too high.
Attempt missed. Farid El Alagui (Hibernian) header from the centre of the box is just a bit too high.
John McGinn (Hibernian) wins a free kick on the right wing.
Foul by Garry Fleming (Dumbarton).
Foul by Farid El Alagui (Hibernian).
Darren Barr (Dumbarton) wins a free kick in the attacking half.
Attempt missed. Jason Cummings (Hibernian) header from the left side of the six yard box is just a bit too high following a corner.
Corner, Hibernian. Conceded by Jamie Lindsay.
Attempt saved. Martin Boyle (Hibernian) header from the centre of the box is saved in the top right corner.
Corner, Hibernian. Conceded by Frazer Wright.
Corner, Hibernian. Conceded by Mark Docherty.
Substitution, Dumbarton. Jordan Kirkpatrick replaces Kevin Cawley.
Foul by Farid El Alagui (Hibernian).
Mark Docherty (Dumbarton) wins a free kick in the defensive half.