Charlton Athletic snatched three points at Griffin Park thanks to a second half goal from Bradley Wright-Phillips.
The npower League One leaders managed to withstand a barrage of Brentford pressure and then stole the points in the second half.
The Bees were utterly dominant for long periods but could not score and were made to pay as the visitors nicked the points.
Brentford started brightly, they had much the better of the first 15 minutes and the game was played predominantly in Charlton's half.
Gary Alexander forced an early save from Charlton goalkeeper Ben Hamer and it took a fine tackle from Michael Morrison to stop the powerful striker latching on to a Clayton Donaldson flick moments later.
Shaleum Logan finished a decent move by slicing a shot well over before Hamer just about beat Donaldson to a delicately chipped Sam Saunders corner.
The hosts had the League One leaders rocking in the first quarter - Niall McGinn saw a shot deflect wide and Leon Legge missed the target with a header.
Charlton had offered little going forward, save a few crosses and set pieces that Richard Lee dealt with easily, but were over-worked in defence keeping Brentford out.
The Bees were better in all departments in the first half hour, but just could not find a way through.
The came within a whisker of scoring when Saunders and Toumani Diagouraga combined to release McGinn on the right, the winger fired in a shot that beat Hamer but bounced back off the far post - the ball flew back in to play but Diagouraga could only turn it over the bar from ten yards.
The visitors started to come back in to the game as the half wore on, led by wide man Danny Green.
The winger bobbled a shot wide and then fired in an effort that Diagouraga deflected wide.
Miguel Llera blocked a Michael Morrison shot before Yann Kermorgant headed a Green long throw over.
But Brentford ended the half as they started it, in the ascendency.
The visitors could not deal with the power of Donaldson and Alexander in attack, Diagouraga was able to play incisive balls in key areas and McGinn and Saunders were pulling the home defence in all directions.
McGinn had a shot blocked before Alexander saw an effort deflect over and Saunders curled a free kick in to a defensive wall.
Donaldson missed a great chance moments before half time when he headed a McGinn cross inches wide after great work on the left by the Northern Ireland international.
Kermorgant missed the target early in the second half for the visitors, who were better in the first ten minutes after the break than they had been before.
Morrison made a superb tackle to prevent Donaldson going through while, at the other end, Lee was called in to action to save outside his penalty area when Wright-Phillips was sent clear.
Unfortunately, in making the save, Lee clattered in to Logan and the defender had to be stretchered off with a head injury after a long period of treatment on the pitch.
Marcus Bean came on as a makeshift right back and the game had barely got back in to a pattern before Charlton took the lead.
Green put a ball in from the right which flew along the six-yard box and Wright-Phillips turned it in from close range.
While Charlton had been better in the second half, the goal was very much against the run of play and, coupled with the loss of Logan, Brentford's pattern was disrupted for a few moments.
But they soon recovered and continued to press Charlton back - Donaldson fired in a shot that deflected wide and then had an effort blocked from a corner.
Brentford introduced Mike Grella and Myles Weston in an attempt to find a way back in to the game and had lots of possession in Charlton territory without creating clear cut openings.
The visitors could have sealed the game with some late chances - Lee saved when a Llera clearance hit Kermorgant and Legge cleared when a corner caused panic in the home defence.
Lee got down well to turn a Wright-Phillips shot around the post and Green shot well over.
Bean dragged a shot wide for The Bees before referee Eddie Ilderton indicated there would be at least ten minutes stoppage time, partly because of the injury to Logan and partly due to Charlton's desire to waste as much time as possible.
Kermorgant had the first chance of the additional time, bringing a fine save out of Lee, but most of the action was at the other end.
Brentford forced a series of corners that the visitors just about scrambled away, Donaldson had an effort deflected wide and Hamer made a great save from a flicked header from Grella.
The goalkeeper saved at Alexander's feet in the dying seconds and that was enough to give Charlton the win.
Brentford: Lee; Logan (sub Bean 63 mins), Legge, Llera, Woodman; McGinn (sub Weston 71 mins), Douglas, Diagouraga, Saunders (sub Grella 80 mins); Donaldson, Alexander
Subs (not used): Devlin, Eger
Bookings: Grella (87 mins), Douglas (90 mins) (sixth of season), Alexander (90 mins) (second of season)
Charlton Athletic: Hamer; Solly, Taylor, Morrison, Wiggins; Green (sub Wagstaff 90 mins), Hollands, Hughes, Jackson (sub Ephraim 76 mins); Kermorgant, Wright-Phillips
Subs (not used): Sullivan, Cort, Hayes
Bookings: Wiggins (85 mins), Morrison (90 mins), Taylor (90 mins)
Attendance: 8,095 (1,830 away fans)
By Chris Wickham