Jay Bothroyd scored a late winner to boost Queens Park Rangers' hopes of staying up and deal a blow to Southampton's own survival prospects.
QPR took the lead against the run of play when Loic Remy finished clinically from Junior Hoilett's lofted pass.
Southampton equalised through Gaston Ramirez, who followed up Julio Cesar's save and chipped the goalkeeper.
But QPR snatched only their third win of the season as Bothroyd turned in a low cross from Park Ji-sung.
In a tense finale, a late corner almost brought about an equaliser for Southampton, but Maya Yoshida's header was brilliantly saved one-handed by substitute goalkeeper Robert Green, who had only just replaced the injured Brazilian Cesar.
- Loic Remy's second Premier League goal came from only his third shot on target
- Julio Cesar is the only goalkeeper to be substituted twice in the Premier League this season.
- QPR scored twice after scoring only four in their previous 10 Premier League games.
Six minutes of injury-time followed before bottom club QPR were able to celebrate a crucial win which moved them to within four points of safety, and left the Saints just three points above the relegation zone.
QPR boss Harry Redknapp punched the air in delight at the conclusion of a difficult afternoon in which he was booed throughout on his first return to Southampton since he sparked fury among the fans by leaving to rejoin arch-rivals Portsmouth seven months after relegation.
The outcome also justified his decision to drop Adel Taarabt and field a new-look strike force, with the recalled Remy, Bothroyd and Hoilett all playing decisive roles.
After being greeted by a chorus of boos as he emerged from the tunnel, the opening exchanges of the match did little to lighten Redknapp's mood as QPR struggled to cope with the home side's pace and movement.
Adam Lallana and Jack Cork both went near from long range, while Jason Puncheon had an appeal for a penalty turned down by referee Howard Webb.
But the momentum shifted as Hoilett and Remy combined to give QPR the lead from their first attack.
Hoilett's pass caught the Saints' defence on the turn and Remy sprinted clear to beat Artur Boruc with a crisp finish, which the retreating Danny Fox narrowly failed to clear off the line.
The goal seemed to energise QPR, who enjoyed a period of control, with Remy a constant threat on the right flank.
A physical encounter claimed its first victim when Saints captain Lallana was forced to leave the field after a collision with Clint Hill, but his replacement Rodriguez provided the spark the home side needed.
His low strike from the edge of the box was parried by Cesar straight into the path of Ramirez, who clipped a sublime finish over the QPR keeper.
"What a result for QPR and what a birthday present for Harry Redknapp. The QPR manager's relief was clear at the final whistle after Bothroyd delivered only their third win in 28 Premier League games."
There was still time for QPR to fashion a chance before half-time as Bothroyd latched on to a loose ball inside the box, but could not find the target with his left-footed drive.
Southampton went on the offensive after the restart with centre-back Jose Fonte firing wide before Rodriguez curled a delightful effort on to the roof of the net.
The right wing remained QPR's most profitable avenue and it was from there that they carved out what proved to be the winning goal.
Park slid in to dispossess left-back Yoshida and crossed from the byeline to Bothroyd, who tapped home his first Premier League goal of the season.
With five minutes on the clock, Yoshida had a golden chance to make amends for his error, rising highest to meet James Ward-Prowse's header.
But Green - brought on in the 73rd minute when Cesar limped off with a thigh injury - pulled off a superb save to keep QPR's slender hopes of beating the drop alive.
Southampton manager Mauricio Pochettino:
"We didn't expect this result but we have to accept it because we have made some mistakes.
"We've tried very hard and put in a great effort to get a different result but because of errors and their keeper's intervention we didn't get a positive result."
"I have confidence in my team, but we need to keep on working for this result and prepare the next game against Norwich."
QPR manager Harry Redknapp:
"It was a big result for us, this is a difficult place to come and Southampton are a good team.
"I picked 11 players to work hard and when you work hard you get your rewards.
I don't see Southampton getting sucked into a relegation battle. They are a good side."
- 31 Boruc
- 02 Clyne
- 03 Yoshida
- 06 Fonte Booked
- 13 Fox (Shaw - 57' )
- 04 Schneiderlin
- 10 Ramirez (Ward-Prowse - 74' )
- 18 Cork
- 20 Lallana (Rodriguez - 43' )
- 42 Puncheon
- 07 Lambert
- 01 K Davis
- 22 Richardson
- 23 Shaw
- 08 S Davis
- 16 Ward-Prowse
- 21 Guly
- 09 Rodriguez
Queens Park Rangers
- 33 Julio Cesar (Green - 74' )
- 03 Traore Booked
- 05 Samba
- 06 Hill
- 19 Bosingwa
- 07 Park Ji-sung
- 14 Granero (Jenas - 53' )
- 40 M'bia Booked
- 18 Remy
- 23 Hoilett
- 37 Bothroyd Booked (Fabio - 90' )
- 01 Green
- 15 Onuoha
- 20 Fabio
- 10 Taarabt
- 16 Jenas
- 29 Townsend
- 12 Mackie
Live Text Commentary
Full Time The final whistle is blown by the referee.90:00 +5:18
Nathaniel Clyne produces a cross.90:00 +4:35
Free kick awarded for a foul by Stephane Mbia on Maya Yoshida. Artur Boruc takes the direct free kick.90:00 +0:56
Free kick awarded for a foul by David Hoilett on Jose Fonte. Artur Boruc takes the free kick.88:35
Rob Green restarts play with the free kick.88:35 Substitution
Substitution Jay Bothroyd goes off and Fabio Da Silva comes on.88:35
James Ward-Prowse challenges Armand Traore unfairly and gives away a free kick.86:58
Rickie Lambert is ruled offside. Indirect free kick taken by Rob Green.86:40
Inswinging corner taken by James Ward-Prowse from the left by-line.86:14
Rickie Lambert delivers the ball, Jose Fonte takes a shot. Save by Rob Green.85:12
Corner taken right-footed by James Ward-Prowse from the right by-line, Maya Yoshida takes a shot. Brilliant save by Rob Green.85:00
Jay Rodriguez takes a shot. Jermaine Jenas gets a block in.84:09
The ball is swung over by Nathaniel Clyne, Jay Rodriguez has a headed effort at goal from close in which goes wide right of the target.83:43
Jay Bothroyd is penalised for handball and concedes a free kick. Jose Fonte takes the free kick.83:21
Luke Shaw sends in a cross, comfortable save by Rob Green.79:09
Luke Shaw takes a shot. Save by Rob Green.78:56
Nathaniel Clyne delivers the ball, Clint Hill makes a clearance.76:46
Assist on the goal came from Ji-Sung Park.76:46 Goal scored
Goal! - Jay Bothroyd - Southamp'n 1 - 2 QPR Jay Bothroyd gets on the score sheet with a goal from close range to the bottom left corner of the goal. Southampton 1-2 QPR.76:39
A cross is delivered by Ji-Sung Park,
The ball is crossed by Jay Bothroyd.74:59
The ball is delivered by Nathaniel Clyne, clearance made by Clint Hill.74:48
The ball is delivered by Nathaniel Clyne, clearance made by Rob Green.73:06 Substitution
Substitution (Southampton) makes a substitution, with James Ward-Prowse coming on for Gaston Ramirez.73:06 Substitution
Substitution Rob Green on for Soares Julio Cesar.72:29
Outswinging corner taken from the left by-line by Gaston Ramirez.71:10
Corner taken right-footed by Jermaine Jenas from the right by-line, Morgan Schneiderlin makes a clearance.70:24
Jay Rodriguez takes a shot. Save made by Soares Julio Cesar.67:14
Gaston Ramirez gives away a free kick for an unfair challenge on Soares Julio Cesar. Soares Julio Cesar takes the direct free kick.66:42
The ball is swung over by Jack Cork, save by Soares Julio Cesar.66:09
Stephane Mbia concedes a free kick for a foul on Gaston Ramirez. Direct free kick taken by Jack Cork.63:07
Luke Shaw delivers the ball.61:37
Morgan Schneiderlin is flagged offside by the assistant referee. Jose Bosingwa takes the free kick.59:08
David Hoilett crosses the ball.58:05
The ball is crossed by Jason Puncheon, save by Soares Julio Cesar.56:33 Substitution
Substitution Daniel Fox goes off and Luke Shaw comes on.54:14
Rickie Lambert takes a shot. Jay Rodriguez has an effort at goal from outside the penalty box which goes wide right of the target. Clint Hill gets a block in.53:58
The ball is delivered by Daniel Fox.52:43 Substitution
Substitution Jermaine Jenas is brought on as a substitute for Esteban Granero.52:33
Centre by Gaston Ramirez, Armand Traore makes a clearance.51:23
Free kick awarded for an unfair challenge on Nathaniel Clyne by David Hoilett. Nathaniel Clyne restarts play with the free kick.50:47
Jose Fonte produces a right-footed shot from long range which goes wide right of the target.50:12
Daniel Fox takes a outswinging corner to the near post, clearance by Armand Traore.48:36
Jose Bosingwa has an effort at goal from outside the penalty area which goes wide right of the goal.47:58
Corner taken by Esteban Granero.47:48
The ball is swung over by David Hoilett, clearance made by Daniel Fox.46:42
Stephane Mbia concedes a free kick for a foul on Gaston Ramirez. Free kick crossed left-footed by Gaston Ramirez from left channel, Clint Hill makes a clearance.45:57
Effort from inside the area by Daniel Fox misses to the left of the target.45:01
The second half begins.45:00 +4:31 Half time
Half Time The match has reached half-time.45:00 +4:06
Jay Bothroyd produces a left-footed shot from deep inside the area which goes wide of the left-hand post.45:00 +3:29
Esteban Granero restarts play with the free kick. Save by Soares Julio Cesar.45:00 +3:29 Booking
Booking Jose Fonte receives a yellow card for unsporting behaviour.45:00 +3:13
Jay Rodriguez takes a shot. Jose Fonte concedes a free kick for a foul on Jay Bothroyd.45:00 +0:52
Assist on the goal came from Jay Rodriguez.45:00 +0:52 Goal scored
Goal! - Gaston Ramirez - Southamp'n 1 - 1 QPR Gaston Ramirez finds the net with a goal from inside the six-yard box high into the middle of the goal. Southampton 1-1 QPR.45:00 +0:49
Jay Rodriguez takes a shot. Save made by Soares Julio Cesar.44:40
Gaston Ramirez restarts play with the free kick.44:40 Booking
Booking Armand Traore is booked.44:30
Free kick awarded for an unfair challenge on Gaston Ramirez by Armand Traore.43:37
Corner taken by Gaston Ramirez from the right by-line to the near post, David Hoilett manages to make a clearance.43:15
Gaston Ramirez takes a shot. David Hoilett gets a block in.42:06 Substitution
Substitution Jay Rodriguez replaces Adam Lallana.40:37
Jay Bothroyd challenges Maya Yoshida unfairly and gives away a free kick. Direct free kick taken by Artur Boruc.39:50
Jason Puncheon concedes a free kick for a foul on Loic Remy. Free kick taken by Jose Bosingwa.39:06
Free kick awarded for an unfair challenge on Daniel Fox by Jose Bosingwa. Daniel Fox takes the direct free kick.33:34
Gaston Ramirez fouled by Stephane Mbia, the ref awards a free kick. Gaston Ramirez takes the direct free kick.32:29
Centre by Jack Cork, save made by Soares Julio Cesar.32:08
A cross is delivered by Nathaniel Clyne, Christopher Samba manages to make a clearance.30:44
The official flags Adam Lallana offside. Soares Julio Cesar restarts play with the free kick.28:15
The ball is sent over by Adam Lallana, Christopher Samba manages to make a clearance.28:04
Centre by Nathaniel Clyne.27:10
Daniel Fox crosses the ball, clearance made by Christopher Samba.27:03
Adam Lallana produces a cross, Christopher Samba makes a clearance.26:17
Unfair challenge on Jose Fonte by Jay Bothroyd results in a free kick. Free kick taken by Artur Boruc.23:04
Direct free kick taken by Daniel Fox.23:04 Booking
Booking Stephane Mbia receives a caution for unsporting behaviour.22:59
Stephane Mbia gives away a free kick for an unfair challenge on Jack Cork.21:16
Outswinging corner taken by Esteban Granero from the right by-line played to the near post, Gaston Ramirez makes a clearance.21:02
Loic Remy takes a shot. Save by Artur Boruc.20:35
Free kick awarded for an unfair challenge on Esteban Granero by Adam Lallana. Jose Bosingwa takes the free kick.18:13
Jack Cork fouled by Esteban Granero, the ref awards a free kick. Free kick taken by Jack Cork.16:44
Gaston Ramirez restarts play with the free kick.16:44 Booking
Booking Jay Bothroyd is cautioned.16:06
Free kick awarded for an unfair challenge on Jack Cork by David Hoilett. Daniel Fox restarts play with the free kick. Jay Bothroyd challenges Nathaniel Clyne unfairly and gives away a free kick.13:59
The assist for the goal came from David Hoilett.13:59 Goal scored
Goal! - Loic Remy - Southamp'n 0 - 1 QPR Goal scored by Loic Remy from deep inside the penalty box to the top right corner of the goal. Southampton 0-1 QPR.13:01
Adam Lallana has shot on goal from just outside the penalty box which goes wide of the right-hand upright.11:32
Jason Puncheon fouled by David Hoilett, the ref awards a free kick. Direct free kick taken by Jason Puncheon.11:00
The ball is delivered by Adam Lallana, clearance by Armand Traore.9:40
Adam Lallana has an effort at goal from outside the penalty box missing to the wide right of the target.7:57
Jack Cork has an effort at goal from outside the box which goes wide left of the goal.6:18
Jason Puncheon challenges Ji-Sung Park unfairly and gives away a free kick. Soares Julio Cesar takes the free kick.4:23
Adam Lallana delivers the ball, clearance by Christopher Samba.3:46
The assistant referee flags for offside against Jay Bothroyd. Free kick taken by Morgan Schneiderlin.2:27
Daniel Fox concedes a free kick for a foul on Loic Remy. Jose Bosingwa takes the direct free kick.0:53
Jason Puncheon sends in a cross.0:36
Jason Puncheon crosses the ball, Jose Bosingwa gets a block in.0:17
Corner taken short by Adam Lallana.0:07
Centre by Adam Lallana, clearance by Christopher Samba.0:00
The ref blows the whistle to begin the match.
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