Arsenal suffered a second consecutive preseason defeat, losing 3-2 to Borussia Dortmund at Emirates Stadium. Dortmund struck early through Samuele Inácio and Konstantinos Karetsas, who both scored in the first half to make it 2-0. Arsenal responded after the break with goals from Ethan Nwaneri and Viktor Gyökeres, but Joane Gadou's strike restored Dortmund's two-goal cushion.

Gabriel Martinelli's stoppage-time equalizer was disallowed for offside, sending the match to penalties where Arsenal won 5-4. Bruno Guimarães made his debut in a £75 million ($101 million) move from Newcastle, greeted by a passionate Emirates crowd. Despite creating chances, Arsenal's defensive lapses and missed opportunities highlighted areas of concern ahead of the new season.

Mikel Arteta will need to address tactical issues as the Gunners prepare for the upcoming campaign.