Overview

• Mats Hummels has announced his retirement from professional football following the conclusion of AS Roma's current season.
• Reports indicate that Borussia Dortmund is exploring the possibility of bringing Hummels back as a standby player for the upcoming Club World Cup in June and July.
• Dortmund has not made any official statements regarding Hummels' potential return to the team as a player.
• The team is addressing defensive challenges, including the prolonged absence of regular starter Nico Schlotterbeck.
• An additional transfer window from June 1 to June 10 allows Club World Cup participants, including Dortmund, to register new players for the tournament.