An early header from Mark Bradley was enough to give Rotherham United the points at Griffin Park.
Brentford were handed their second straight home loss when the right back arrived late to meet a Ben Pringle free kick and head home from close range.
That proved to be the only goal of the afternoon and came just 14 minutes in.
The visitors defended it robustly, often straying the wrong side of the tight physical line they walked.
But they managed to repel everything Brentford could throw at them and left with the win.
A sign of how the afternoon was to proceed came inside the first seconds when Rotherham launched the ball straight down the middle from the kick off.
They tried not to stray far from that modus operandi for the rest of the afternoon.
Brentford had to try and win the physical battle and earn the right to play.
They did it for long periods but when the chances came they were not taken and that proved to be their undoing.
Lee Frecklington shot wide early on for the visitors while Clayton Donaldson forced Scott Shearer in to a low save after bundling past a posse of defenders before the early goal.
The first 25 minutes were largely a midfield battle; Brentford failed to get their foot on the ball and spent too much time playing Rotherham’s direct game.
They came close to an equaliser when Donaldson found Marcello Trotta in the box but the striker’s shot flew wide after a sharp turn.
Alex Revell lashed over for Rotherham and Ben Pringle shot well wide before David Button saved well from Matt Tubbs.
After around 30 minutes a football match broke out.
Adam Forshaw and Toumani Diagouraga started to take control of the centre of midfield, Brentford mopped up the second balls and the game became a better spectacle.
Rotherham started playing more football too but Brentford were more adept at moving the ball quickly and began to open the visitors up.
Shearer made a fine save from Donaldson after the striker had been sent through by Forshaw and he denied Sam Saunders soon after.
Forshaw was within a whisker of equalising with a left foot shot after nice work by Trotta and the striker then forced Kari Arnason to make an important block after turning well in the box.
Brentford had control at the end of the first half and were even more dominant in the second.
Manager Uwe Rösler brought on Will Grigg and moved Alan McCormack to be part of a three-man central midfield.
Most of the second period was played in Brentford’s attacking areas and the chances came.
Dean headed wide twice before Grigg also missed the target with an aerial effort.
Forshaw had a shot blocked after a burst in to the box before a Logan effort was blocked and Saunders fired over.
Rotherham were largely defending in number and playing on the counter attack.
They were effective at doing it and had chances to seal the win.
Kieran Agard had a shot blocked and Tubbs missed the target from the left channel after Revell headed on.
Revell also went close after escaping from Martin Taylor; his shot went across the face of goal.
But most of the action was at the other end.
A Diagouraga shot hit Harlee Dean when a corner was half cleared and from a cross soon after, Grigg headed on and Donaldson was just unable to reach to head in.
Saunders had a pair of shots blocked while, on the break, a Danny Hylton effort deflected wide and Pringle missed the target with a shot.
Saunders had another effort deflected wide after a run forward and Farid El Alagui’s header from the resulting corner was saved while Frecklington shot wide at the other end.
Shearer made a superb save in the dying seconds to tip a rising George Saville shot over the bar and that proved to be Brentford’s last chance.
Late penalty appeals were waved away by referee Oliver Langford and when he blew his whistle for the last time, Rotherham had the points.
Brentford: Button; Logan, Dean, Taylor, Craig; Saunders, Diagouraga (sub El Alagui 70 mins), Forshaw, McCormack (sub Saville 76 mins); Trotta (sub Grigg h/t), Donaldson
Subs (not used): Lee, Nugent, Douglas, Fillo
Bookings: McCormack (34 mins) (second of season)
Rotherham United: Shearer, Bradley, Morgan, Arnason, Skarz; Agard, Frecklington, Milsom (sub Tidser 83 mins), Pringle; Tubbs (sub Hylton 62 mins), Revell (sub Eaves 86 mins)
Subs (not used): Collin, Brindley, Mills, Rowe
Bookings: Agard (24 mins), Milsom (36 mins), Frecklington (40 mins), Bradley (68 mins), Revell (82 mins), Pringle (90 mins)
Attendance: 6,614 (516 away fans)
By Chris Wickham