Tuesday's Champions League match in Dortmund, between German club Borussia Dortmund and Monaco-based AS Monaco was postponed when $4, injuring center-back Marc Bartra.
Police later confirmed that three explosions went off in the area of the team bus.
The bus was on the way to the stadium for the match where fans had already gathered.
When news of the explosion reached the stadium, Monaco supporters showed their solidarity with their hosts by chanting "Dortmund! Dortmund! Dortmund!" Dortmund fans stood and applauded the gesture.