Neil Warnock earned his first win as Leeds United manager as first-half goals from Robert Snodgrass and Luciano Becchio saw off fellow Championship play-off hopefuls Middlesbrough.
Victory failed to lift the 10th-placed visitors up the table but it may have reignited their fading top six hopes.
Rhys Williams' second-half header was the best chance for Boro, who remain fourth after a lacklustre home display.
And Barry Robson's late dismissal ended their hopes of an unlikely comeback.
"There's change happening at Leeds United and it appears to be change for the better. But it was a disappointing day for Middlesbrough.
Leeds now trail sixth-placed Cardiff by four points, having played at least one game more than most of their rivals.
Four wins in their last five outings had catapulted Tony Mowbray's Boro up to fourth after stumbling out of the play-off picture with a barren New Year spell of six matches without a win.
But history was not in Boro's favour ahead of the Riverside clash, having not yet beaten Leeds at home since moving from Ayresome Park in 1995.
And Boro become the architects of their own downfall, a livid Mowbray watching errors from Jason Steele and Justin Hoyte gift Leeds a two-goal advantage.
Snodgrass, made skipper by Warnock in one of his first acts since becoming Leeds boss, scored the opener, stroking home from 18 yards after being coolly picked out by a composed Aidy White's short square pass.
Darren O'Dea smashed a deep free-kick towards White in the right channel, the Leeds winger brushing off a feeble challenge from Boro left-back Joe Bennett to set up Snodgrass, whose sidefoot shot squirmed underneath Steele.
Under previous boss Simon Grayson, Leeds had no problems with their attacking incisiveness. But they had became rather toothless in front of goal in the three games since Warnock started prowling the Whites' touchline last month.
Having enjoyed the first goal of his reign, the much-travelled manager was celebrating another within 10 minutes when Hoyte's mis-kick allowed top scorer Ross McCormack to pull back and Becchio gleefully rolled home from close range.
Warnock's priority since arriving in West Yorkshire has been plugging a leaky defence, who have conceded more goals than any other top half team.
DID YOU KNOW?
Middlesbrough have not beaten Leeds United in 10 attempts since moving to the Riverside in 1995.
Despite their lofty position Boro hardly have a prolific strike-rate and failed to really stretch away keeper Andy Lonergan.
Midfield schemer Barry Robson was Boro's brightest spark in an otherwise dull home first-half performance and his fierce volley did stir Lonergan into punching clear.
And, seconds later, the Scot's goalbound corner was bravely headed off the line by United debutant Paul Robinson as Boro finally woke from their slumbers as the game approached the break.
Mowbray's no doubt harsh half-time words galvanised Boro as they set about Leeds with renewed purpose in the early stages of the second half.
Williams escaped his marker from a home free-kick but wastefully planted his header into Andy Lonergan's side-netting.
Boro huffed and puffed as they tried to make Leeds sweat before Robson blew his top by kicking out at Adam Clayton on 86 minutes.
He received his marching orders - ending Mowbray's hopes of salvaging an unlikely point as organised Leeds claimed a third clean sheet in four games since Warnock's arrival.
VIEW FROM THE DRESSING ROOM
Leeds boss Neil Warnock on BBC's Match of the Day:
"It's good to finally get a goal - and obviously the win.
"I thought the crowd was fantastic and it was great to get off the mark.
"I thought we played quite well in the first three games but there were some great performances out there today."
Live Text Commentary
Full Time The referee brings the game to a close.90:00 +6:09
Adam Hammill has an effort at goal from 25 yards. Andy Lonergan makes a fantastic save. Close range shot by Seb Hines misses to the left of the target.90:00 +5:18
Unfair challenge on Justin Hoyte by Danny Webber results in a free kick. Adam Hammill restarts play with the free kick.90:00 +5:01 Substitution
Substitution Danny Pugh on for Adam Clayton.90:00 +3:23
Jason Steele takes the direct free kick.90:00 +3:23 Substitution
Substitution Mikael Forssell is brought on as a substitute for Luciano Becchio.90:00 +3:23
Robert Snodgrass concedes a free kick for a foul on Bart Ogbeche.90:00 +1:19
Corner taken by Adam Hammill.90:00 +1:13
The ball is delivered by Adam Hammill, clearance made by Darren O'Dea.90:00 +0:34
Robert Snodgrass challenges Adam Hammill unfairly and gives away a free kick. Nicky Bailey restarts play with the free kick.89:55
Robert Snodgrass fouled by Adam Hammill, the ref awards a free kick. Robert Snodgrass takes the free kick.89:21
Short corner taken by Robert Snodgrass from the left by-line.87:36
Adam Hammill gives away a free kick for an unfair challenge on Adam Clayton. Free kick taken by Andy Lonergan.86:53 Substitution
Substitution Ross McCormack goes off and Danny Webber comes on.85:44
Direct free kick taken by Joe Bennett.85:44 Dismissal
Dismissal Barry Robson sent from the field by the ref for violent conduct.85:30 Booking
Booking Adam Clayton is cautioned.85:01
Adam Clayton gives away a free kick for an unfair challenge on Barry Robson.84:17
Short corner taken by Robert Snodgrass from the left by-line.83:51
Effort on goal by Ross McCormack from 18 yards. Save made by Jason Steele.
Bart Ogbeche takes a shot. Save by Andy Lonergan.82:34
The ball is crossed by Bart Ogbeche, save made by Andy Lonergan.81:49
Michael Brown challenges Marvin Emnes unfairly and gives away a free kick. Direct free kick taken by Barry Robson.81:16
Adam Hammill produces a left-footed shot from just outside the box that misses to the right of the net.80:20
The ball is delivered by Marvin Emnes, Close range headed effort by Curtis Main goes wide of the left-hand post.79:52
The ball is crossed by Adam Hammill, blocked by Paul Connolly.75:20
Jason Steele takes the free kick.75:20 Substitution
Substitution Bart Ogbeche joins the action as a substitute, replacing Kevin Thomson.75:20
Kevin Thomson fouled by Adam Clayton, the ref awards a free kick.75:07
Shot by Adam Clayton. Matthew Bates gets a block in.74:35
Inswinging corner taken left-footed by Robert Snodgrass played to the near post, clearance by Matthew Bates.74:31
The ball is delivered by Aidan White, clearance by Joe Bennett.74:17
Robert Snodgrass produces a cross.73:42
The ball is crossed by Adam Hammill, clearance made by Darren O'Dea.73:18
The ball is sent over by Barry Robson, clearance made by Robert Snodgrass.73:04
The ball is swung over by Justin Hoyte, Tom Lees makes a clearance.72:45
Kevin Thomson restarts play with the free kick.72:45 Booking
Booking Paul Connolly goes into the referee's book for unsporting behaviour.72:40
Paul Connolly gives away a free kick for an unfair challenge on Adam Hammill.71:58
Nicky Bailey has an effort at goal from just outside the box which goes wide of the right-hand upright.71:50
Joe Bennett sends in a cross, clearance made by Adam Clayton.71:29
The ball is crossed by Aidan White.70:16
Adam Hammill crosses the ball.69:42
The referee blows for offside. Matthew Bates takes the indirect free kick.68:50
Kevin Thomson challenges Robert Snodgrass unfairly and gives away a free kick. Paul Robinson takes the direct free kick.67:39
Effort from outside the area by Adam Clayton goes wide right of the goal.65:54
Ross McCormack is flagged offside by the assistant referee. Free kick taken by Jason Steele.64:11
Unfair challenge on Matthew Bates by Luciano Becchio results in a free kick. Joe Bennett takes the direct free kick.63:45
Barry Robson crosses the ball.62:22 Substitution
Substitution Kevin Thomson replaces Lukas Jutkiewicz.62:04 Substitution
Substitution Curtis Main on for Rhys Williams.61:23
Robert Snodgrass produces a header from inside the area that goes over the bar.60:06
Inswinging corner taken from the left by-line by Ross McCormack, Nicky Bailey makes a clearance.59:53
Shot by Adam Clayton. Seb Hines gets a block in.56:33
Free kick awarded for a foul by Adam Clayton on Barry Robson. Direct strike on goal from the free kick comes in from Adam Hammill, blocked by Tom Lees.56:00
Free kick awarded for an unfair challenge on Adam Hammill by Michael Brown. Free kick taken by Joe Bennett.54:46
Rhys Williams gives away a free kick for an unfair challenge on Aidan White. Tom Lees takes the free kick.52:22
Headed effort from close range by Rhys Williams goes wide left of the target.51:50
Free kick awarded for an unfair challenge on Lukas Jutkiewicz by Darren O'Dea. Barry Robson takes the free kick.50:09
Adam Hammill sends in a cross, clearance made by Tom Lees.49:13
Robert Snodgrass produces a left-footed shot from outside the box and misses left.48:25
Inswinging corner taken by Barry Robson from the right by-line, comfortable save by Andy Lonergan.45:01
The game restarts for the second half.45:00 +4:54 Half time
Half Time The ref blows to end the first period.45:00 +4:31
Corner taken by Ross McCormack, clearance made by Matthew Bates.45:00 +3:43
Seb Hines concedes a free kick for a foul on Luciano Becchio. Ross McCormack produces a shot on goal direct from the free kick, clearance made by Matthew Bates.45:00 +2:08
The official flags Lukas Jutkiewicz offside. Andy Lonergan takes the free kick.45:00 +1:33
Joe Bennett produces a cross, clearance made by Darren O'Dea.44:12
Free kick awarded for an unfair challenge on Robert Snodgrass by Barry Robson. Direct free kick taken by Paul Robinson.43:09
Free kick awarded for a foul by Lukas Jutkiewicz on Paul Robinson. Free kick taken by Robert Snodgrass.40:35
Shot from outside the box by Ross McCormack misses to the left of the goal.39:33
Headed effort from deep inside the penalty area by Matthew Bates misses to the left of the goal.39:01
Free kick awarded for an unfair challenge on Lukas Jutkiewicz by Darren O'Dea. Direct free kick taken by Barry Robson.38:37
Aidan White takes a shot from just inside the penalty box which clears the crossbar.37:57
Unfair challenge on Ross McCormack by Joe Bennett results in a free kick. Paul Robinson takes the free kick.37:45
Corner taken right-footed by Adam Hammill, clearance made by Paul Robinson.37:10
Effort from 20 yards by Adam Hammill. Blocked by Michael Brown.36:26
Luciano Becchio is caught offside. Matthew Bates takes the free kick.35:13
Shot on goal by Luciano Becchio from just inside the area goes over the target.34:23
Joe Bennett gives away a free kick for an unfair challenge on Aidan White. Paul Connolly restarts play with the free kick.33:41
Corner taken left-footed by Barry Robson from the right by-line to the near post, clearance by Paul Robinson.33:29
Shot by Barry Robson. Brilliant save by Andy Lonergan.30:01
A cross is delivered by Barry Robson, blocked by Paul Robinson.29:46
The ball is swung over by Marvin Emnes, Tom Lees makes a clearance.28:54
Free kick awarded for a foul by Luciano Becchio on Matthew Bates. Direct free kick taken by Jason Steele.28:00
Joe Bennett challenges Luciano Becchio unfairly and gives away a free kick. Ross McCormack takes the direct free kick.26:58
Assist on the goal came from Ross McCormack.26:58 Goal scored
Goal! - Luciano Becchio - Middlesbro 0 - 2 Leeds Luciano Becchio fires in a goal from inside the six-yard box to the bottom right corner of the goal. Middlesbrough 0-2 Leeds.26:55
Ross McCormack produces a cross,25:27
Effort from 20 yards by Barry Robson. Adam Hammill gets a block in.24:11
Foul by Darren O'Dea on Lukas Jutkiewicz, free kick awarded. The free kick is swung in left-footed by Barry Robson, Tom Lees manages to make a clearance.22:37
The official flags Luciano Becchio offside. Seb Hines takes the indirect free kick.22:24
Justin Hoyte sends in a cross, Paul Robinson gets a block in.21:21
The ball is delivered by Adam Hammill, save by Andy Lonergan.20:40
The referee blows for offside. Jason Steele restarts play with the free kick.17:53
Assist by Aidan White.17:53 Goal scored
Goal! - Robert Snodgrass - Middlesbro 0 - 1 Leeds Robert Snodgrass scores a goal from just outside the area to the bottom right corner of the goal. Middlesbrough 0-1 Leeds.17:08
Ross McCormack sends in a cross, comfortable save by Jason Steele.15:17
Shot from just outside the area by Marvin Emnes goes over the bar.14:57
Robert Snodgrass challenges Barry Robson unfairly and gives away a free kick. Direct free kick taken by Nicky Bailey.14:17
Foul by Adam Clayton on Rhys Williams, free kick awarded. Jason Steele restarts play with the free kick.10:45
Effort on goal by Nicky Bailey from 35 yards went harmlessly over the net.9:38
Handball decision goes against Luciano Becchio. Jason Steele takes the free kick.9:17
Ross McCormack crosses the ball.8:06
Ross McCormack produces a right-footed shot from just outside the box that misses to the right of the target.6:55
Luciano Becchio gives away a free kick for an unfair challenge on Seb Hines. Seb Hines restarts play with the free kick.4:23
Rhys Williams challenges Luciano Becchio unfairly and gives away a free kick. Direct effort from the free kick comes in from Robert Snodgrass.2:31
Shot by Adam Clayton. Blocked by Matthew Bates.2:19
Robert Snodgrass delivers the ball.0:34
The referee penalises Barry Robson for handball. Andy Lonergan takes the free kick.0:25
Joe Bennett sends in a cross.0:00
The match begins.
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