The Bees have struck in the first minute three times already this season, with Bryan Mbeumo at the forefront.
O'Neil said: “It’s incredible. Obviously, they're big on set plays and they use kick-off as a start of that, but the lads have seen all three, so they know. There's a lot of things that need to fall into place for them to score from all of them, but we know we need to be ready.
“We talk about the start of the game all the time, no matter who we play, but I guess the three goals in consecutive weeks sort of heightens that awareness of how important the start of this game will be.”
Asked about a plan for Mbeumo, he also stated: “Not really, because he's been moved around quite a bit. They've got some injury issues and we're not sure who's going to be available, so he's been used as a nine, he's been used off the side, so we know what threat he can be, and we know his individual ability.
“But to know exactly where he's going to be and who's going to be up against him is difficult at the moment. As always, it’s been more of a group/team focus on how we get the better of Brentford, rather than too much on individuals versus individuals.”