GROSSED OUT: Arsenal torn apart by Brighton on horror afternoon for Mikel Arteta's reigning champions - 5 talking points

Arsenal slumped to their first Premier League defeat of the season after being humbled 3-0 by in-form Brighton on Saturday.

Pascal Gross gave the Seagulls the lead just after the half-hour mark with a brilliant effort. Charalampos Kostoulas doubled the home side's advantage with an eye-catching goal of his own.

Fabian Hurzeler's men took full control after the break through Chema Andres. It leaves Brighton flying high in third, just two points behind the Gunners heading into the first international break of the season.

Here are all of the talking points from the Amex Stadium:

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After threatening early on through Kostoulas - David Raya intervening - Brighton scored a deserved opener through Gross. The defending from the Gunners left a lot to be desired, with the German midfielder picking up the ball just outside of the penalty area.

And he let fly with a low effort that beat the Arsenal goalkeeper at his near post. It also saw the former Dortmund man extend his recent run of brilliant form, Gross now with four goals in five games in all competitions. Alongside his assist for Andres' goal, he had another hugely impressive afternoon.

The decision to bring the 35-year-old back to the Amex Stadium looks more and more like a masterstroke each week.

If Arsenal were kicking themselves after Gross' goal, boss Mikel Arteta would have been even more annoyed after the Seagulls extended their advantage on the stroke of half time.

Yasin Ayari was given far too much space to run unchallenged into the Arsenal half. He picked out Greek forward Kostoulas, he took a touch, span and fired home a low effort that beat Raya again.

After just two goals during his debut campaign at Brighton, he now has doubled that record this term and will be hopeful of extended that form throughout the season.

Arsenal's afternoon got even worse after their own weapon was used against them clinically just before the hour. From a corner, Chema Andres got free from his marker and had the simple task of nodding home.

Raya had some complaints and made them known to the referee but those appeals fell on deaf ears.

The goal also saw Brighton score their 16th goal in the Premier Leagye already this season - no other side have scored more.

Given how sensational Arsenal have been over the past few years, this really was a shocking performance. Their midfield struggled to get to grips with the Brighton press and they looked vulnerable every single time they were on the ball.

Their defence also looked wide open throughout the 90 minutes which is very un-Arsenal like. And it all contributed to the Gunners being beaten by three goals for the first time since May 2023, that defeat also coming at the hands of Brighton.

One defeat does not spell disaster for Arsenal but Arteta will be concerned at the real lack of fight that his side showed on the South Coast.

Eyebrows were raised this summer when Brighton decided to fork out a club record £46m for Luka Vuskovic from Spurs this summer.

But that looks like many very well spent. After a brilliant season with Hamburg, the Croatian has enjoyed a very impressive start to life with his new employers. And he looked every inch of a near £50m defender against Arsenal.

Given his former Tottenham alliances, the win and clean sheet will feel even more satisfying.