Mainz 05
Borussia DBorussia Dortmund began their new season with a convincing 2-0 victory
German champions claim the first major trophy of the campaign
The Gunners were unable to add another title to their collection
The 24-year-old has put pen to paper on a contract that will keep him at the Catalan club until the summer of 2031
The occasion carried extra significance as fans said goodbye to club stalwart
