Farid El Alagui’s 88th minute header gave the Bees a deserved victory against Colchester United in a game which the Bees had enough chances to win three times over.
The Moroccan met Harry Forrester’s pin-point cross with an un-stoppable header to give the Bees back-to-back home wins.
El Alagui, Clayton Donaldson and Toumani Diagouraga had all been guilty of wasting guilt-edged chances earlier in the game.
The Bees made two changes from the draw with Walsall with Jake Bidwell and Adam Forshaw replacing Scott Barron and Kevin O’Connor, who both dropped to the bench.
It was a bright start from the home team as Clayton Donaldson headed an early chance over the bar after patient work on the right by Adam Forshaw.
The Bees then squandered two golden chances in as many minutes through Toumani Diagouraga and Clayton Donaldson.
The first came after good battling work by Farid El Alagui freed Donaldson down the right and he squared the ball to an un-marked Diagouraga whose heavy touch forced him wide and he could only fire into the side netting from ten yards.
Two minutes later it was Donaldson’s turn to be wasteful in front of goal. Simon Moore’s long punt up-field was flicked on by El Alagui releasing the big striker into acres of space. However, Donaldson snatched at the chance and fired it high over the bar from fifteen yards.
Brentford went close again on eighteen minutes when Sam Saunders whipped in a free-kick which Donaldson could only head tamely into Mark Cousins arms under pressure from Tom Eastman.
Adam Forshaw was the next to try his chances but his 25 yards drive fizzed across the face of goal evading El Alagui and Donaldson
The visitors were struggling to get a foothold in the game and Moore was a virtual spectator for the opening half-hour but he had to be alert to prevent the Bees falling behind from Colchester’s first foray into Brentford territory.
A long clearance forward released Ian Henderson. Despite strong suspicions of off-side the linesman kept his flag down and Moore stayed big to block the Colchester man’s fierce drive from ten yards.
The visitors had another chance three minutes later but Henderson scuffed his shot wide after Freddie Sears cross deflected off Tony Craig and perfectly into his path.
Donaldson nearly gave the Bees the lead in fortuitous circumstances after 34 minutes when he charged down Cousins clearance but the ball floated harmlessly over the bar.
Saunders was then booked for a deliberate trip on Sears as the former West Ham man looked the break clear.
In a frantic 30 second spell the Bees peppered the Colchester goal looking for the opener. Firstly Shaleum Logan’s 20 yards effort was deflected inches wide for a corner.
The resulting corner wasn’t cleared and Harlee Dean had two efforts cleared before Jonathan Douglas saw his effort blocked by the defender with Adam Forshaw putting the re-bound just over from 30 yards.
Despite the Bees pressure they should have gone in behind at half-time. Anthony Wordsworth’s beautiful curling free-kick was met by Eastman at the back post but he could only head wide from five yards.
Colchester then almost caught the Bees napping at the start of the second-half.
Douglas went over in the box appealing for a penalty, which Stuart Attwell turned down, leaving the Bees short in midfield. Colchester broke and the ball found its way to Sears at the back post but he well denied by Moore.
Uwe shuffled his pack shortly after; removing the ineffectual Saunders and replacing him with Forrester.
The change almost paid dividends as the Bees broke with Forrester flicking the ball onto Donaldson who beat Magnus Okuonghae before bearing down on Cousins goal. However the big striker’s touch let him down and Cousins was out quickly to save at his feet.
Cousins was called into action again 60 seconds later when he somehow kept out Douglas’s point-blank header from Logan’s teasing cross.
Forrester then whistled an effort wide from 30 yards as the Bees continued to dominate.
Donaldson and Forshaw were both withdrawn, replaced by Paul Hayes and debutant Tom Adeyemi, as Uwe Rösler tried to freshen up the team.
As the game wore on the conditions began to take their toll and in the sweltering heat the pace of the game slowed to a crawl.
The minutes ticked towards a frustrating score-less draw and when El Alagui passed up another chance, hitting Cousins from twelve yards after Cousins’s poor kick had fallen to his feet, it seemed destined to end as a draw.
But with stoppage time approaching Harry Forrester swung in a perfect cross which El Alagui outmuscled Eastman to reach, and the Bees striker made no mistake from six yards.
Brentford: Moore; Logan, Craig, Dean, Bidwell; Douglas, Forshaw (sub Adeyemi 69 mins), Diagouraga, Saunders (sub Forrester 51 mins) ;Donaldson (sub Hayes 63 mins), El Alagui
Subs not used: Lee, O'Connor, Barron, Legge.
Bookings: Saunders (36 mins) (2nd of season)
Colchester United: Cousins; Wilson, Okuonghae, Coker, Eastman; Wordsworth (sub Morrison 89 mins), Bean, Bond, Izzet; Sears, Henderson.
Subs not used: Pentney, Rose, Heath, Massey, White, Sanderson.
Attendance: 5,499 (342 away)