Dortmund police chief Greogor Lange has said "everything humanly possible" will be done to ensure Borussia Dortmund's rearranged match against Monaco passes without incident.
The Champions League fixture, originally scheduled for Tuesday, was put back to Wednesday evening after three explosions targeted Dortmund's team coach around six miles from Signal Iduna Park.
Windows on the bus were shattered and defender Marc Bartra was taken to hospital where he underwent surgery on a broken bone in his wrist on Tuesday evening.
Several thousand fans were already inside Dortmund's Westfalenstadion ahead of the game, where visiting Monaco supporters chanted "Dortmund" in a show of solidarity.
The rearranged fixture will take place at 5.45pm UK time on Wednesday, with increased security measures in place.
"The stadium and the surrounding area remain the focal point for police," said Lange.
"We're preparing a major police presence for tomorrow and will do everything humanly possible to ensure the match can take place safely."
The decision to postpone was made after a meeting held at the stadium between European football's governing body UEFA, representatives of the two clubs and local authorities.
UEFA president Aleksander Ceferin was "deeply disturbed" by events in Dortmund and backed the decision to reschedule the match.
He said in a statement: "I was deeply disturbed by the explosions which occurred in Dortmund. The decision taken to postpone the UEFA Champions League match between Borussia Dortmund and AS Monaco was the correct one since we must always prioritise the safety and security of all fans, team officials and players."
The Dortmund players returned to their hotel following the explosions.
Dortmund police also revealed a letter had been found, claiming responsibility for the incidents.
