The Magpies failed to return to winning ways, as they went down 2-1 to already-relegated QPR at Loftus Road in London.
Emmanuel Riviere put visiting Newcastle in the lead midway through the first half, but Rangers scored twice in the space of seven minutes after the break.
Matt Phillips headed home the equaliser from Charlie Austin's cross in the 54th minute, and Leroy Fer smashed in a superb winner from 25 yards just past the hour mark.
Rangers were brilliant in the second half and deservedly picked up all three points, while once again John Carver’s side failed to hold onto their advantage.
Former Newcastle forward Quinn was following the match, and he was far from pleased with the performance produced by a team that has now gone 10 games without success.
Newcastle’s final game of the season is against West Ham United at St. James’ Park next Sunday.
The Magpies find themselves 17th in the Premier League table at the moment with 36 points from 37 matches, just two points above Hull City, meaning they could still be relegated to the Championship if fate conspires against them.