A second-half brace from striker Chris Dagnall saw managerless Barnsley shock promotion hopefuls Leeds at Oakwell.
A dominant performance from the relegation-threatened hosts was rewarded as Dagnall scored a penalty after he was fouled by Sam Byram.
Dagnall continued to torment the young Leeds full-back and Byram was at fault again as the 26-year-old burst past him to fire a low shot past Paddy Kenny.
Chants of "Time to go!" were aimed at boss Neil Warnock by angry Leeds fans.
The Tykes began sharply and tested visiting goalkeeper Kenny with a deflected strike from Jim O'Brien within two minutes.
This was followed by a penalty shout from Stephen Dawson when he appeared to be fouled by Leeds striker Luciano Becchio.
Barnsley continued to pile on the pressure, with Harewood then striking the foot of Kenny's right-hand post as he cut inside from the left.
The start of the second half saw a brief improvement for Leeds as Barkley dragged a 25-yard shot wide, before the Everton loanee then hit the crossbar with a powerful drive from six yards.
The momentum soon swung back in Barnsley's way, however, thanks to Dagnall's deserved double.
The result sees Barnsley move off the foot of the table, while Leeds slip five points behind the final play-off spot.
Barnsley caretaker manager David Flitcroft, talking about his future: "I have found out a lot about myself in the last 10 days, it could change the way I look at myself for the rest of my career as when you lead a group and they are all playing for you, it's different.
"If I get sacked, I get sacked, but I've been taught well and you don't walk out on people. I told them [the players] at half-time I was excited about it [the [performance] as we overran and dominated Leeds.
"I wanted to spend some time with the players and celebrate with them after the game, especially someone like Chris Dagnall. I worked with him at Rochdale where he got 24 in a season for us and I picked some music and put the goals to it and showed him before kick-off."
Leeds manager Neil Warnock, who brought a laptop into the press conference to complain about a refereeing decision, said: "We were very poor in the first half and if I had have been one of the 5,000 I might have said what they were.
"I thought we had some great chances at the start of the second half and then there was a horrendous tackle from [Stephen] Dawson. How that's not a red card I don't know.
"I think I'm doing a great job if I'm honest and with one or two additions that I've got lined up... I understand their [the supporters'] disappointment but we know we need to strengthen."
- 01 Steele
- 03 Golbourne
- 15 McNulty
- 25 Cranie
- 33 Kennedy
- 34 Stones
- 07 Dawson
- 08 O'Brien (Mellis - 33' )
- 11 Perkins
- 13 Dagnall (Noble-Lazarus - 90' )
- 16 Harewood
- 12 Alnwick
- 02 Hassell
- 06 Foster
- 21 Mellis (Rose - 88' )
- 23 Etuhu
- 24 Noble-Lazarus
- 32 Rose
- 01 Kenny
- 02 Peltier
- 05 Pearce
- 15 Tate
- 08 Austin
- 18 Tonge
- 19 Norris (McCormack - 46' )
- 20 Barkley
- 25 Byram
- 10 Becchio Booked
- 21 Diouf (Green - 51' )
- 12 Ashdown
- 04 Lees
- 07 Green
- 11 Varney
- 14 White
- 28 Somma
- 44 McCormack
Live Text Commentary
Full Time The referee blows for the end of the match.90:00 +2:41 Substitution
Substitution Chris Dagnall leaves the field to be replaced by Reuben Noble-Lazarus.90:00 +2:25
Paul Green has an effort at goal from outside the penalty box which goes wide right of the target.89:03
Direct free kick taken by Luke Steele.89:03 Booking
Booking Booking for Luciano Becchio for unsporting behaviour.88:58
Luciano Becchio challenges Tom Kennedy unfairly and gives away a free kick.86:49 Substitution
Substitution Danny Rose joins the action as a substitute, replacing Jacob Mellis.86:49
David Perkins fouled by Luciano Becchio, the ref awards a free kick. Direct free kick taken by Tom Kennedy.84:05
Marlon Harewood has shot on goal from just outside the area which goes wide of the right-hand upright.82:51
Shot from long range by Ross McCormack misses to the right of the target.78:27
Shot by Ross Barkley from outside the box goes high over the target.77:28
Jacob Mellis takes a corner.76:57
Marlon Harewood produces a right-footed shot from the edge of the area and misses to the left of the target.73:07
Ross Barkley has shot on goal from just outside the area which goes wide of the right-hand upright.70:55
Chris Dagnall fouled by Alan Tate, the ref awards a free kick. Jacob Mellis takes the free kick.69:31
The referee blows for offside. Free kick taken by Patrick Kenny.67:19
Samuel Byram concedes a free kick for a foul on Jacob Mellis. Tom Kennedy restarts play with the free kick.65:17
Assist on the goal came from Marlon Harewood.65:17 Goal scored
Goal! - Chris Dagnall - Barnsley 2 - 0 Leeds Utd Chris Dagnall gets on the score sheet with a goal from inside the penalty area to the bottom right corner of the goal. Barnsley 2-0 Leeds.62:42 Goal scored
Goal! - Chris Dagnall - Barnsley 1 - 0 Leeds Utd Placed penalty scored by Chris Dagnall. Barnsley 1-0 Leeds.
Penalty awarded for a foul by Samuel Byram on Chris Dagnall.59:10
Free kick awarded for a foul by Ross McCormack on Jacob Mellis. Tom Kennedy crosses the ball in from the free kick, clearance by Michael Tonge.58:34
Outswinging corner taken by John Stones, clearance made by Ross Barkley.57:31
Paul Green gives away a free kick for an unfair challenge on David Perkins. Jacob Mellis crosses the ball from the free kick right-footed from right channel, Patrick Kenny makes a save.56:20
Ross Barkley takes a shot.55:38
The referee blows for offside against Marlon Harewood. Patrick Kenny takes the free kick.54:54
Luciano Becchio concedes a free kick for a foul on Jimmy McNulty. Direct free kick taken by Tom Kennedy.52:39
Free kick awarded for an unfair challenge on Rodolph Austin by Jacob Mellis. Free kick crossed right-footed by Ross McCormack from right channel, Martin Cranie makes a clearance.51:21
The assistant referee signals for offside against Marlon Harewood. Indirect free kick taken by Patrick Kenny.50:55
Free kick awarded for an unfair challenge on Chris Dagnall by Rodolph Austin. David Perkins takes the free kick.50:29 Substitution
Substitution Paul Green replaces El-Hadji Diouf.49:39
Jason Pearce fouled by Chris Dagnall, the ref awards a free kick. Direct free kick taken by Patrick Kenny.48:22
Ross Barkley produces a left-footed shot from outside the penalty box and misses right.47:50
Chris Dagnall produces a right-footed shot from just outside the penalty area that goes harmlessly over the target.45:01
The referee blows his whistle to start the second half.45:01 Substitution
Substitution (Leeds) makes a substitution, with Ross McCormack coming on for David Norris.45:00 +2:03 Half time
Half Time The ref blows to signal half-time.45:00 +2:02
The ball is delivered by Marlon Harewood.45:00 +1:45
David Norris concedes a free kick for a foul on John Stones. David Perkins restarts play with the free kick.45:00 +0:39
David Perkins challenges Ross Barkley unfairly and gives away a free kick. Direct free kick taken by Lee Peltier.45:00 +0:12
David Perkins takes a short corner.44:53
Short corner worked by John Stones.43:45
El-Hadji Diouf challenges Luke Steele unfairly and gives away a free kick. Direct free kick taken by Luke Steele.41:39
Alan Tate concedes a free kick for a foul on Chris Dagnall. Scott Golbourne takes the direct free kick.41:20
The referee blows for offside. Direct free kick taken by Tom Kennedy.40:17
Chris Dagnall has an effort at goal from just outside the box which goes wide of the right-hand upright.38:28
Jacob Mellis takes the outswinging corner, Luciano Becchio makes a clearance.35:51
Foul by Chris Dagnall on David Norris, free kick awarded. Patrick Kenny takes the free kick.33:05
Jason Pearce fouled by Marlon Harewood, the ref awards a free kick. Free kick taken by Patrick Kenny.32:25 Substitution
Substitution Jacob Mellis joins the action as a substitute, replacing Jim O'Brien.28:04
Unfair challenge on Michael Tonge by David Perkins results in a free kick. Free kick taken by Alan Tate.27:43
The referee gives a free kick against Michael Tonge for handball. David Perkins takes the free kick.26:57
Shot from outside the penalty box by Michael Tonge goes wide right of the goal.25:58
Jim O'Brien is caught offside. Patrick Kenny takes the free kick.25:40
Jim O'Brien takes a short corner.24:45
Effort from inside the area by Chris Dagnall misses to the right of the goal.24:01
Corner taken by Jim O'Brien from the right by-line played to the near post, clearance by Alan Tate.22:39
Shot by Jim O'Brien. Save by Patrick Kenny.20:50
Foul by Martin Cranie on El-Hadji Diouf, free kick awarded. The free kick is swung in right-footed by Lee Peltier, save by Luke Steele.19:28
Outswinging corner taken by Jim O'Brien from the right by-line, Header from inside the area by Martin Cranie strikes the post.17:38
Corner taken right-footed by Jim O'Brien to the near post, clearance by Michael Tonge.14:04
Marlon Harewood challenges David Norris unfairly and gives away a free kick. Direct free kick taken by Patrick Kenny.12:52
Foul by Luciano Becchio on Scott Golbourne, free kick awarded. Free kick taken by Tom Kennedy.12:03
Stephen Dawson takes a shot. Patrick Kenny makes a save. Marlon Harewood produces a right-footed shot from just outside the area that hits the post.11:22
Jim O'Brien challenges Ross Barkley unfairly and gives away a free kick. Direct free kick taken by Lee Peltier.7:43
Shot on goal by Jim O'Brien from just inside the area clears the crossbar.6:26
Headed effort on goal by Luciano Becchio from inside the penalty box misses to the right of the target.5:10
Foul by Stephen Dawson on Samuel Byram, free kick awarded. Alan Tate restarts play with the free kick.3:07
Free kick awarded for an unfair challenge on Jason Pearce by Chris Dagnall. Patrick Kenny takes the free kick.1:58
Short corner taken by Jim O'Brien.1:35
Outswinging corner taken right-footed by Jim O'Brien from the right by-line, Alan Tate manages to make a clearance.1:17
Jim O'Brien takes a shot. Save made by Patrick Kenny.0:00
The game kicks-off.
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