In response to Russia's invasion of Ukraine, world football governing body FIFA ruled that the contracts of foreign players would be suspended until the end of the 2021/22 season, effectively giving them free agent status so they can train with other clubs.
On Monday, Raymond Frimpong Owusu and Alan Aussi - on the respective books of Zorya Lugansk and the Dynamo Kyiv reserves until a few weeks ago - took part in training at Dortmund for the first time. A third unnamed player was also involved.
"The bombs and rockets fell - I could hear them. The war was getting closer and closer, and I got scared. Then I decided to flee," Owusu told Ruhr Nachrichten of his journey from Ukraine, via Poland, to Dortmund.
"And now I'm training here at Borussia Dortmund, and took a photo with Erling Haaland after training. That's crazy!"
Bundesliga and Bundesliga 2 clubs have been sending clear messages of peace and solidarity since the start of the war, with one-off shirts, blue-and-yellow captain's armbands and banners, pre-match moments of reflection and other actions.
Engagement has also been expanded in the form of targeted donation campaigns from several players, while the DFL has already made €1 million available for humanitarian support.
"The people of Ukraine are of concern to all of us and need our help," said Dortmund defender Mats Hummels. "BVB and I offer our support."
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