Mikel Arteta elected to rest several key players for the start of a busy December schedule, yet it took just 11 minutes for the Gunners to open the scoring, with two of his squad players combining to bring about the goal.
A clever flick from Noni Madueke released Ben White on the overlap, who lifted a cross into the box for Arsenal’s top scorer in all competitions, Mikel Merino, to head into the ground and over the line.
Madueke then worked the space for a close-range shot that was beaten away by Caoimhin Kelleher, before Brentford responded with a bright period, in which David Raya was forced to tip Kevin Schade’s header from a corner onto the crossbar.
The Bees had found a foothold in the contest, but the hosts maintained plenty of threat leading up to half time, with Rico Henry making vital interventions to deny Madueke twice in quick succession.
First, a low ball across goal from Declan Rice was smothered by a sliding Henry as Madueke was primed to turn home, then Henry made a challenge at a crucial moment to stop the Arsenal winger from pulling the trigger inside the area.
Momentum was firmly with Brentford after the restart, and the tension inside the Emirates was intensifying as the PL's second top scorer, Igor Thiago, entered the fray as part of a triple change with just one goal separating the sides after an hour.
Arteta didn’t wait to respond, bringing on Eberechi Eze and Bukayo Saka, as Arsenal grew into the half. Riccardo Calafiori and Rice each called Kelleher into action with shots from range, with the latter effort almost leading to the game’s second goal, only for Merino to turn wide on the follow-up as he failed to adjust.
The Gunners kept pressing as Kelleher kept out Calafiori and was alert to a Saka miskick on the rebound, shortly before the substitute atoned by staying onside to power a shot past the goalkeeper, whose palm couldn’t prevent the game from slipping away.
Victory restoring Arsenal’s five-point lead at the top of the PL standings, having still only lost once in the league (W10, D3). Arteta is now unbeaten in his last nine H2Hs (W7, D2), with this result leaving Brentford in midtable, having failed to win 20 of their last 24 PL London derbies (D6, L13).
Flashscore Man of the Match: Mikel Merino (Arsenal)