The first chance fell to the visitors, and it was a golden opportunity in truth. A cross from the right fell to Rico Henry who had got forward well. With the goal at his mercy though, he made poor contact inside the six-yard box and the ball bobbled well wide.
Oleksandr Zinchenko had our first sighter at goal. A half-cleared corner fell invitingly for the Ukrainian, but he blazed his shot well over from 15 yards out.
Brentford were remaining compact and organised in defence though, while possessing the threat of Bryan Mbeumo and Ivan Toney on the break.
The two of them so nearly combined to break the deadlock midway through the half. Mbeumo cut the ball back for Toney who sidefooted against the bar. It was a let off after we afforded the Bees top scorer too much space inside the box.
Ben Mee had a header from a corner blocked as they continued to grow in confidence.
The west Londoners are unbeaten in their past nine Premier League games, and on this evidence you could see why.
Toney underlined their confidence with a swirling shot from 25 yards that Aaron Ramsdale had to bat away.
As half-time approached our best move of the game to that point resulted in Gabriel Martinelli volleying just over from Granit Xhaka’s laid off header.
We came out with a renewed energy after the break. Bukayo Saka and Martin Odegaard both had shots comfortably saved by David Raya.
On the hour mark Mikel Arteta turned to his bench, bringing on Trossard. Within five minutes the Belgian had his first Gunners goal.
Saka shrugged off his marker on the right, sent a low cross in to the far post where Trossard tucked into the net. A vital breakthrough and the crowd erupted.
Our lead lasted less than ten minutes though. We failed to deal with a free kick into the box, and after the ball pinged around, it fell to Toney, who couldn’t miss.
We were back to square one, and had to try to break down the Brentford defensive block once again.
Despite speculative efforts from Zinchenko and Thomas Partey, we couldn’t find a way through, and had to make do with just a point from a hard-fought encounter – only the second time we’ve dropped points at home this season.