Joe Ledley's early header was enough to give Derby a lead at the break in a fiery first half at Griffin Park.
The Rams made the early running and took the lead when the former Crystal Palace man headed home after Sam Winnall knocked the ball back across goal.
Gary Rowett's side were happy to make niggly fouls and Tom Lawrence was booked before an altercation between Ryan Woods, Bradley Johnson and Andre Wisdom. The former two were lucky not to be dismissed with referee Andy Davies issuing a yellow card all round.
Brentford had the bulk of possession but were unable to seriously test Scott Carson in the Rams' goal.
Below is how the home side rated at the break.
Bentley 6 Not had a lot to do this half, and little he could do about the goal as the defence stood still expecting an offside flag.
Dalsgaard 6 Not a lot has gone down his side really, but did put in a useful cross which Watkins headed wide late in the half.
Henry 6 A lot is going down his side and he is getting involved but final delivery is lacking, and lost his man for Derby's goal.
Barbet 5 Not really pushed on from his fantastic cameo at Bolton thus far.
Bjelland 7 The better of the two centre backs so far, has looked fairly solid and made some good passes.
Woods 6 Not his best half in a Bees shirt by a longt stretch and lucky to escape with a booking after raising his hands and appearing to slap a Derby player during a touchline scuffle.
Yennaris 6 Been busy but not able to make a breakthrough as yet.
Sawyers 5 One of his more languid games so far – needs to up the tempo as this sort of game can have no passenger.
Clarke 5 One of his quieter halves, hopefully more to come after the break.
Maupay 6 Toiled hard up front but not had a lot fall for him. High balls into the box are gobbled up by the Derrby defenders, and balls into feet have seen him allowed little time or space.
Watkins 7 Looking like Brentford's best hope in this game – looked dangerous in attack and unlucky both with a cross-shot across the face of goal and a deflected effort which flew just wide.