Relegation is still a real possibility for the Magpies - who are without a win in ten games - going into the final day of the Premier League season next weekend
Newcastle United missed the chance to secure their Premier League survival as Leroy Fer's magnificent winner gave already-relegated QPR a 2-1 victory at Loftus Road.
John Carver's visitors had ended a run of eight straight defeats with a 1-1 draw against West Brom last week and they opened the scoring on Saturday through Emmanuel Riviere's 24th-minute strike.
Riviere's first Premier League goal - which finally came after 18 hours and four minutes in a black and white shirt - could have been enough to see Newcastle ensure safety due to Hull City's 2-0 defeat at Tottenham.
But QPR - who saw goalkeeper Robert Green forced off with a head injury sustained in a collision with team-mate Joey Barton - stormed back in the second half to claim a first home win of 2015.
Midfielder Matt Philips levelled in the 54th minute with a close-range header before Fer's spectacular winner made sure of the points.
Fer took advantage of Newcastle's carelessness in possession with a fierce long-ranger that flew beyond Tim Krul, meaning that the Tyneside club will go into their final-day meeting with West Ham just two points clear of third-bottom Hull, who finish the season against Manchester United.
Riviere broke his duck with the first real clear-cut chance. The former Monaco man found the net with a scrappy finish that deflected off his left leg and beyond Green after sloppy defending from QPR had allowed him to latch on to a seemingly innocuous long ball forward from Krul.
Newcastle naturally grew in confidence following the opener and went close to adding a second when Ryan Taylor curled a free-kick narrowly wide of the left-hand post.
There were worrying moments for QPR in the 31st minute when Green was caught in the head by the knee of team-mate Barton as the midfielder came back to help clear the danger from a promising Newcastle attack. Green was able to walk off the pitch but was replaced by Alex McCarthy.
The substitute was called into action to prevent Newcastle from scoring again, getting down low to his right to keep out Fabricio Coloccini's diving header at the far post.
QPR boss Chris Ramsey made his final two changes at half-time by throwing on Reece Grego-Cox and Yun Suk-young in place of Steven Caulker and Junior Hoilett.
And the hosts almost levelled two minutes after the restart when Phillips' effort was deflected wide by Jonas Gutierrez after good work down the right from Charlie Austin. Austin himself then lashed a shot off target from close range following more poor defending.
QPR finally got the goal their early second-half play deserved when Phillips rose highest to convert from Austin's excellent far-post cross.
And the turnaround was the completed in stunning fashion seven minutes later when Fer capitalised on a poor Krul clearance to find the top corner with a rasping drive from 30 yards.
Phillips wasted a golden chance for a third by blazing a shot over with the goal at his mercy, but it mattered little as QPR stood firm to set up a nervous final day for Newcastle.