David McGoldrick's 65th-minute penalty earned Sheffield United a 2-1 victory at QPR in the Sky Bet Championship.
The Blades came from behind at Loftus Road after Ebere Eze had fired Rangers ahead just before the half-hour mark, but Billy Sharp equalised a couple of minutes before the interval by tapping in Kieron Freeman's pull-back from the right.
Only a minute after coming on as a substitute, striker McGoldrick was adjudged to have been nudged in the back by Jake Bidwell at the far post.
McGoldrick, signed on a free transfer after leaving Ipswich this summer, calmly steered his spot-kick past keeper Matt Ingram.
Luke Freeman was instrumental in the move which led to the opening goal, evading two challenges en route to the edge of the United penalty area.
The ball was shifted out to Bidwell and after the left-back's low cross was cleared only as far as Eze, the teenage forward blasted past keeper Dean Henderson from 18 yards out.
Rangers, in their first home match under new boss Steve McClaren, had looked uncomfortable in possession and were pinned in their own half for much of the early stages, with United looking much the better side.
However, QPR nevertheless went close to scoring twice before eventually taking the lead. Henderson kept out a sizzling volley from Eze, who was teed up by Idrissa Sylla tidily laying off Paul Smyth's cross, and moments later Bidwell's cross was headed over by Massimo Luongo.
And after Freeman led a Rangers counter-attack and set up Eze, Henderson was called into action again, this time to block the youngster's fierce shot.
But Henderson was unable to keep Eze at bay - and the goalscorer almost doubled QPR's lead when he dragged a left-footed shot narrowly wide, again after fine work from Freeman.
Just as the visitors seemed to be fading, Sharp rounded off a slick move by firing into an unguarded net.
United, beaten in both their previous games this season, were on top for most of the second half and would have gone ahead sooner had Ingram not produced a fine save to deny Leon Clarke.
Rangers, who have lost both their first two games under McClaren, rarely looked like finding an equaliser. Bright Osayi-Samuel, sent on as a half-time substitute, shot into the side netting and Luongo headed Eze's cross well wide.
The exciting Eze went closer with a powerful drive that was pushed away by Henderson, who also kept out an injury-time effort from Josh Scowen.
Steve McClaren: "We've lost the game because of two poor decisions. The first goal was offside because Sharp was in front of our defenders when the ball was crossed. I can't understand the penalty. We feel McGoldrick is handling Joel Lynch and Bidwell is behind, just ducking to get out of the way. There's no contact.
"It's cost us the game. There's no doubt about that. In terms of the performance I was delighted. I asked the players to go out and be brave and I felt they did that."
Chris Wilder: "Noise and nonsense or whatever it is, we have to keep our cool and go through these periods - it happens to us all. The expectation levels have gone through the roof over the past two years. We've done some things over the two years we like to think have been quite good.
"When you fall a little bit, which we have done in certain periods of the two games, you have to take it on the chin what people say. It wasn't the most free-flowing performance. But it was a Sheffield United type of performance, with guts, determination, desire and a little bit of football played in there."