Villa took the lead courtesy of a deft finish from Danny Ings in the first-half but the Bees then turned the match on its head, with Yoane Wissa equalising in sublime fashion before Mads Roerslev prodded home the winner in the 83rd minute.
Gerrard addressed the media after the mach — these were his most noteworthy quotes.
On the overall performance
The visitors on the day certainly had the better of the opening 45 minuted, fairly dominant in possession and getting enough shots on goal to extend their advantage after Ings' opener — the manager was baffled that, despite such a shrewd first-half display, his side went in level at the break thanks to a curling effort from Wissa.
"I couldn't believe we were only level at half-time, our performance first-half was really strong," said Gerrard. "We played with dominance and control and it was just a matter of when the second goal was going to come, so that was a bit of a head-scratcher."
The second-half was a much tighter affair with neither team willing to risk surrendering another goal, but it would be Brentford who got the lucky break when Emi Martinez parried Roerslev's first effort straight back to him and the Dane duly finished with his second bite at the cherry.
Gerrard was disappointed to lose in such a manner and believes his side could and should have dealt with the attack which ultimately proved their downfall.
"For the second goal we were passive, we didn't defend two or three situations well enough as a team. Since I've been here I've seen that these are players who want to put their bodies on the line but I didn't see any of that for the second goal."
On final third struggles
With Brentford so lacklustre in the first-half, this was perhaps a match that Villa should have put to bed before their opponents would even have got the chance muster their rhythm.
As Gerrard highlights here, Emi Buendia was playing exceptionally in a free role behind Ings and he and other forward-minded players were causing the Bees serious headaches in the first-half, but what was lacking the precision sometimes of the finish, but more often of the decisive final pass.
Buendia showed craft and ingenuity for Ings' opener — spinning away from Christian Norgaard before slipping the striker through on goal — but it wasn't to be seen again from Villa for the rest of the encounter, and that frustrated Gerrard.
"I thought over the 90 minutes we created enough to score more than one goal," he asserted. "Buendia was inventive and creative today and Ings looked back at his best. You've got to score more than one goal, especially with the chances we created.
"We did really well to get into certain positions on the pitch but at this level you've got to execute. At 1-0 up we were in a comfortable place in the game and then they score out of nothing which is the head-scratcher."
This wasn't Villa at their absolute strongest in terms of personnel — there was no Ollie Watkins in the matchday squad, the game came too soon for Ashley Young who is nearing a return to action after fracturing his toe, and skipper Tyrone Mings missed out through suspension.
Nonetheless, Gerrard felt there was enough quality in his side on the day to see Brentford off — a notion likely encouraged by such an assured showing in the majority of the first-half — and is disappointed with how there encounter panned out.
"We had four of five players not available today for different reasons, you're always gonna miss their attributes all over the pitch but I thought we had enough quality in the team we picked to win the game. We should never have lost, worst-case it's a draw. You're always gonna miss your players but that's not an excuse."