QPR showed they have character to match their skills on a bitterly cold rain-lashed afternoon at Chesterfield.
Rangers had to overcome a committed home outfit and awful conditions to win a game that strengthens their play-off chances.
Both teams had players missing through injury but it was Chesterfield's absentees at the back that proved the most significant.
Rangers exploited the inexperience, but Chesterfield still pushed the Londoners all the way and the match was still in the balance until two late goals settled it.
Glynn Hurst had given Chesterfield a great start by heading in a Chris Brandon cross in the 11th minute, but just two minutes later Richard Pacquette turned and drilled in the equaliser.
Poor marking at a corner allowed Danny Shittu to head Rangers in front but they had to wait until six minutes from time to extend that advantage.
With only one goal in it Chesterfield always threatened to get back in the game and they should have equalised in the 76th minute.
Hurst burst through the middle and although Nicky Culkin saved his low shot, the rebound fell kindly for Andy Rushbury, but he put the ball wide.
Rangers took a firm grip on the match in the 84th minute when Paul Furlong latched on to a long ball over the top, held off Stuart Howson and placed a low shot into the bottom left-hand corner.
As Chesterfield pushed men forward, Rangers hit them on the break in the 89th minute when Pacquette slipped the ball through for Andy Thomson to finish clinically with a low right-foot shot from 12 yards.
But Chesterfield at least had the last word when Rangers were punished for relaxing. Hurst was given time to turn and shoot and although Culkin pushed the ball on to the post, Brandon followed up to lift the rebound into the net.