Leeds continued their slump down the Sky Bet Championship table as Brentford won 3-1 at Griffin Park in a game defined by goalkeeping mistakes.
Leeds 'keeper Andy Lonergan dropped the ball straight at the feet of Neal Maupay to give the Brentford striker a simple finish, before Ollie Watkins failed to double the home side's lead from the penalty spot just before half-time.
Brentford 'keeper Daniel Bentley committed a howler to allow Egzijan Alioski to equalise for Leeds midway through the second half before the hosts won it with two late goals, the first a low free-kick from Yoann Barbet followed by a late drive from Ryan Woods.
The result was Leeds' seventh defeat in nine games and leaves them mired in mid-table, while Brentford climb into the top half.
Alioski and Saiz started up front for Leeds. Watkins was in for Brentford.
Dean Smith's side, who had risen to 15th having recovered from a run of seven winless games, had Leeds on the back foot from the off and nearly went ahead after two minutes when Watkins failed to capitalise from a close-range header as the visitors' defence dithered.
Leeds briefly rallied with Samuel Saiz looking lively on the left of a three-man attack, but it was Brentford who went close again on 12 minutes when Barbet sent a free-kick curling inches past Lonergan's post from 25 yards.
Watkins tested Lonergan with a fierce drive from range on the quarter-hour mark, but the Leeds 'keeper was found wanting when he allowed Barbet's high cross to fall out of his hands and straight to the feet of Maupay who could hardly miss.
Leeds should have been two behind when Jansson felled Maupay as the striker steadied himself to shoot moments before the break, but Watkins skied his penalty.
Brentford: Bentley (5), Bjelland (6), Jozefzoon (7), Yennaris (7), Maupay (7), Watkins (7), Egan (6), Woods (8), Sawyers (7), Clarke (7), Barbet (7)
Subs: Mepham (6) Mokojto (6) Vibe (6)
Leeds: Lonergan (5), Ayling (6), Cooper (7), Jansson (7), Berardi (6), O'Kane (7), Phillips (6), Vieira (6), Alioski (7), Saiz (7), Lasogga (7)
Subs: Grot (6) Roofe (7) Hernandez (7)
Man of the match: Ryan Woods
The visitors were reprieved when Bentley in the Brentford goal misjudged a high ball and as it dropped to Alioski the Macedonian looped a fine header into the empty goal.
Nico Yennaris came close to winning it for Brentford when his 30-yard strike hit the crossbar, but it was Barbet's whipped free-kick which put Brentford back in front with five minutes to go before Woods finished off Leeds in stoppage time with a drilled finish from the edge of the box.
Dean Smith: "I felt first half we dominated the game. The penalty would have given us a good enough cushion to have gone and won the game comfortably. But fair play, second half they came out and made it a really tough game for us. I thought the last 15-20 minutes we stepped it up again and press them a lot higher."
Thomas Christiansen: "I believe we deserved much more. I saw the strength in the team, we made two changes at half time and the team went out, believed in the possibility to turn the result round, and we were almost able to do it. In this league, when we make individual mistakes, you get punished."
Man of the match - Ryan Woods
Woods was a constant menace to a Leeds side that never settled into any rhythm at Griffin Park. Strong in the tackle and creative in attack, Woods encapsulated an impressive display from Brentford as they heaped more misery on Thomas Christiansen.
Brentford travel to Cardiff next Saturday at 3.00pm while Leeds play at home to Middlesbrough on Sunday at 1.15pm on Sky Sports Football.