QPR took a vital step towards Premier League survival and inflicted further damage on Tottenham's hopes of a top four finish with a crucial victory at Loftus Road.
Adel Taarabt's first-half free-kick gave Mark Hughes' side the win that gives QPR a crucial three-point cushion between them and the relegation places - but Spurs' slump continues as they now face a fight to earn a place in next season's Champions League.
Taarabt marred his match-winning display when he was shown a second yellow card late on for kicking the ball away - but QPR held out to add Spurs to a list of Loftus Road victims that includes Chelsea, Liverpool and Arsenal.
As Hughes punched the air repeatedly in delight at the final whistle, there was only despair for Spurs counterpart Harry Redknapp as he watched his side struggle in vain to find the inspiration that earned them a place in the top four for so long this season.
Spurs enjoyed plenty of possession but failed to exert concerted pressure as a decline that coincided with Redknapp being touted as potential successor to England coach Fabio Capello extended their recent run to one league win in their last nine games.
They were without Emmanuel Adebayor, who had a hamstring injury, while Redknapp also decided to drop Aaron Lennon to the bench and hand attacking responsibilities to Jermain Defoe.
QPR had proved their threat with those recent home victories over Liverpool and Arsenal - and the game plan was clear as they ensured Spurs were denied time and space to get the creators Luka Modric and Gareth Bale on the ball.
It worked in the early stages, although Spurs settled enough for QPR keeper Paddy Kenny to be forced to save from Bale's header and Rafael van der Vaart's rising angled effort in quick succession.
Spurs, however, were looking hesitant in defence with both goalkeeper Brad Friedel and his defenders displaying signs of real uncertainty - and they fell behind after 24 minutes.
The visitors were unhappy when referee Mark Clattenburg penalised Sandro when he battled for possession with Taarabt, and were feeling an even greater sense of grievance when he curved a low free-kick beyond Friedel from 25 yards as he dived away to his right.
Spurs were showing little of the rhythm and pace that had been their trademark earlier in the season and wasted an opportunity to draw level when Defoe headed over after Kenny could only push out Van der Vaart's powerful effort.
And Redknapp reacted with a positive move at the restart, replacing Sandro with Lennon in an attempt to give Spurs better balance and greater penetration.
Spurs also introduced Danny Rose for Benoit Assout-Ekotto as they continued to spend time in QPR territory but his first contribution was a defensive one as he blocked superbly when Bobby Zamora turned in the area and shaped to shoot only 10 yards out.
The frustration was mounting for Spurs as the game entered the last 20 minutes, even more so when Van der Vaart collected a loose ball in the area but fired wastefully over the top, beating the turf in his annoyance at an opportunity missed.
QPR's defensive defiance was tested even further with 12 minutes left when Taarabt was shown a second yellow card by referee Mark Clattenburg, who had infuriated the home fans seconds earlier by declining to punish Scott Parker despite delivering a lengthy lecture after a theatrical fall.
Spurs continued to apply pressure but Kenny made late saves from Modric and Van der Vaart to spark scenes of elation around Loftus Road after another impressive win.
QPR boss Mark Hughes:
"It was a great goal from Adel and he showed his ability once again. I thought as a performance he was really disciplined in his approach to his defensive role.
"He knew it was a key element of what we were tying to do today in terms of tracking the runs of Kyle Walker and he did it really well, it doesn't come naturally to him but he did it."
Hughes on his side's survival hopes:
"I just think when we come here there is a determination and I think away from home we've been possibly guilty of being a little bit passive on our travels and not being able to create the intensity we have here.
"It will (go to the last game). We have got three games left - three very difficult games. We must try in the last two (away) games, we have to address our away form."
Tottenham manager Harry Redknapp:
"We had enough of the ball and enough chances - I don't think Brad Friedel has had a save to make in all honesty, we just couldn't score.
"We just couldn't get the break, we just needed a bit of luck in front of goal today."