Could Arsenal’s shock 3-0 defeat at Brighton prove to be an early warning in their Premier League title defence?

The Gunners suffered their first league defeat of the season on Saturday as Brighton delivered a clinical display at the Amex Stadium, ending Arsenal’s perfect start.

Pascal Groß opened the scoring in the 31st minute, curling a composed finish beyond David Raya after linking up with Charalampos Kostoulas.

Brighton then doubled their advantage at the break, with teenage forward Kostoulas finding the net to leave Arsenal two goals down.

The home side continued to punish Arsenal after the interval and added a third in the 57th minute when new signing Chema Andrés headed home from Groß’s corner.

Arsenal had entered the fixture with a 100 per cent league record, having won their opening four matches. The defeat means their run of victories has come to an abrupt end, while Brighton remain unbeaten after five league games.

The result also represents a significant statement from Brighton, who were celebrating their 125th anniversary with a victory over the reigning champions.

For Mikel Arteta, the defeat will raise questions about Arsenal’s defensive performance after Brighton repeatedly exposed gaps and created opportunities in the final third.

Groß was particularly influential, scoring once and providing the assist for Andrés’ third goal as Brighton took advantage of their opportunities.

Arsenal remain on 12 points, while Brighton moved onto 10 points after five matches. Manchester City can move clear at the top if they win their upcoming fixture.

The international break now gives Arteta time to assess the problems exposed by Brighton before Arsenal return to Premier League action.