Arsenal succumbed to a 2-0 loss at the hands of the Premier League's new boys Brentford on Friday night.
With no Alexandre Lacazette and Pierre-Emerick Aubameyang, the Gunners had Folarin Balogun up top and also gave new signings Ben White and Albert Sambi Lokonga their official debuts.
The Bees had the Gunners under pressure inside 11 minutes after Bryan Mbeumo ran onto a ball towards the area before going on to smack the face of the outside the post with a snap shot.
Ten minutes thereafter, the Bees had the lead courtesy of Sergi Canos who worked an opening from a tight angle in the area to find the net after the Gunners failed to deal with a corner-kick.
Mbeumo should've put Brentford two goals up just before the half-hour mark from a smart opening off a tight situation in the area, but he drilled the resultant effort wide of target.
The Bees were on the back-foot five minutes in the second half and watched Emile Smith Rowe getting in a central position outside the area to get a shot away, which goalkeeper David Raya saved.
Mikel Arteta made a substitution towards the middle of the second stanza in an attempt to liven up the Gunners with Bukayo Saka introduced in the place of Balogun.
However, this intervention didn't unsettle the Bees, who 17 minutes from time doubled their lead after Christian Norgaard leaped on the end of a throw-in to head in from the back-post.
Arsenal were prevented a consolation in the last four minutes after Raya stretched across the near post to palm Nicolas Pepe's first-time effort behind.
The Bees sat deep in the closing periods to see out an opening day victory on their return to the top-flight of English football.
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