Carlisle though started the better in the game and had the first real chance after four minutes when Kevan Hurst raced forward before laying possession off to Richard Keogh. The rampaging right-back then striking in a fierce drive which was well parried away by Brentford's Arsenal-loanee goalkeeper Wojciech Szczesny, Dickson then completing the clearance.
Polish stopper Szczesny then making an even better save four minutes later from a Tom Taiwo volley after a Scott Dobie knock down. The visitors then had a good shout for a penalty turned down on 19 minutes by inconsistent referee Roger East when Keogh looked to have been brought down by Dickson inside the box. Joe Anyinsah then having two shots in quick succession, one wide and one held by Szczesny as United kept up the pressure.
Matty Robson then blazed a long range free-kick miles over the top for Carlisle before the Bees started to come back into it a little with John Bostock and Kevin O'Connor both having shots blocked. Brentford though did take the lead slightly against the run of play just after the half-hour mark when they worked a quick free-kick through Bostock that saw Charlie MacDonald push in a low cross for Weston to side-foot home from close range.
Harte and Legge then heading wide at opposing set-pieces as the game became more end to end. Another quickly taken free-kick saw the Bees breaking again on 43 minutes, Weston's cross in seeing Bostock's shot hacked away off the line by Carlisle left-back Evan Horwood. Legge then firing a powerful drive wide with the last chance of the first-half.
It was Brentford's turn to start well after the interval and Bostock had a shot well blocked by Keogh before then slamming another effort over Blues goalkeeper Adam Collin's crossbar. Bostock very busy looking for a goal as then shot wide before in the 55th minute his effort on goal was parried out into the path of Weston, the winger able to knock the ball home from 15 yards out to make it 2-0 to the home side.
Bostock was a one-man shooting machine for Brentford and he struck yet another effort in which was pushed away, this time to safety, by Collin, before Harte clipped a free-kick just over the top for the visitors and then struck another effort narrowly wide. Szczesny was called into action moments later though when Keogh's powerful cross-shot was touched on by United substitute Richard Offiong, the Polish goalkeeper reacting well though to make a low full length stop and hold.
The Bees then thought they had made it 3-0 when Weston's shot, from a MacDonald pass, pinged back off the post, referee East though had already whistled for a foul though by the time MacDonald and Ben Strevens were looking to knock home the rebound. Carlisle did though get back into the game on 81 minutes through one of a good few poor decisions by Salisbury-based official East.
Dobie going clear through the middle only to go down under an excellent challenge from Legge which clearly won the ball. East gave a penalty though and then made the decision even worse by bizarrely only booking Legge when if it was a spot-kick in his eyes then surely it was a red card offence. Harte though didn't make a mistake as he duly dispatched the penalty with ease.
Harte then shot wide from distance as Carlisle looked for a late equaliser but it was soon Brentford back at it again when Sam Wood and Weston both struck in off-target efforts. Szczesny then made an easy catch from a looping Offiong header before the Bees made sure of all three points in injury time, Dickson having his first shot blocked before being able to lash home the rebound. Danny Foster then almost making it 4-1 with the last kick of the game but Collin was able to tip his shot around the post.