QPR's players celebrate Liam Kelly's penalty save against Leeds
Leeds boss Marcelo Bielsa denied that nerves were affecting his team after they lost at QPR to miss the chance to go top of the Championship.
Nahki Wells' controversial first-half goal earned QPR all three points over a Leeds side that finished with 10 men after Kalvin Phillips' late sending off.
Bielsa's side also saw Patrick Bamford's second-half penalty saved as they slipped to back-to-back league defeats for the first time this season.
But they were rightly aggrieved by QPR's winner as Eberechi Eze's free-kick struck both of Wells' arms before he tapped into the net from six yards.
Leeds dominated possession in the second half but were unable to force an equaliser, with Pablo Hernandez hitting the post with a free-kick as their poor record in London was extended to one win in their past 19 visits to the capital.
And they ended the game a man short as midfielder Phillips was shown a straight red card for a reckless late challenge on Geoff Cameron. Phillips now faces a three-game ban.
Asked if anxiety had been a factor in recent performances, Bielsa said: "I don't think that, but it's clear that we have not taken advantage of our chances. We have to have a lot of chances to score one goal.
"I don't think there's a lack of confidence or that it's about nerves. There were moments where we lacked efficiency but I don't think this happened because of a lack of confidence.
"In football you have lots of situations you can manage and some you can't manage.
"Sometimes the ones you can't manage damage one team or are in favour of one team. Today, everything that we couldn't manage in the game was against us."
Leeds remain a point behind leaders West Brom, but the gap between them and the play-off spots remains four points following Brentford's goalless draw at Huddersfield.
They now only have one victory in seven league games, having won their previous seven, and they struggled against Rangers' high-octane first-half approach.
Luke Amos saw an effort from 20 yards palmed away by Leeds keeper Kiko Casilla and Ilias Chair dragged a shot wide, either side of Wells firing them in front after the dangerous Bright Osayi-Samuel had been tripped by Hernandez.
Leeds had a penalty appeal waved away after Helder Costa appeared to be felled in the box by Lee Wallace, while Bamford lobbed their best first-half effort over the bar from 20 yards after expertly turning his marker.
Bielsa's side dominated the second half as Liam Cooper and Jack Harrison both headed off target soon after the restart.
And after Bamford saw his spot-kick turned round the post by Liam Kelly, having been being tripped by the Rangers keeper, Phillips had a long-range effort well saved.
QPR manager Mark Warburton: "We were good in the first half and I thought we deserved the lead at half-time.
"We got too deep in the second half and invited them onto us. They're a very good team and we rode our luck a bit.
"But so much credit to the players and the way they stood up, to a man. Leeds are a highly talented team.
"So much pleasure was taken by the players from today's performance because that type of game, defensively, you do have to stand up.
"Sometimes you do have to win ugly. Today you saw a QPR team that have won nice games but this time won in ugly fashion. That's heartening for all of us."
