Germany head coach Joachim Loew and his French counterpart Didier Deschamps admit still being haunted by memories of the November 2015 terror attacks in Paris.
World champions Germany host France in Cologne with the events of two years ago still casting a shadow.
On November 13, 2015, suicide bombers set off explosive devices outside the Stade de France during Germany's match with France that was the start of a series of terror attacks that left 130 dead.
Loew and the stunned Germany squad were forced to spend the night at the stadium in Paris during a security crackdown.
"You do not forget something like that. The memories return again and again," said Loew at a press conference on Monday.
"That was a dramatic experience and one you wouldn't want to go through again.
"You manage to block things out a bit, but it (the evening) was marked by a fear of being inside the stadium."
France coach Didier Deschamps, who was also in charge of his national team on that fateful night, said the hosts were equally affected by the Paris attacks.
"I'll never forget how it was at the stadium, we were scared, there were tears," said the 1998 World Cup winner.
"I'll never forget the wave of solidarity which followed."
Deschamps revealed the French squad held a minute's silence before their final training session in Cologne on Monday to remember those who died two years ago.
Cologne will be on red alert, as a third of the tickets for Tuesday's match at the Rhein-Energie-Stadium have not been sold and a ring of security will be thrown around the ground.
Loew said he feels safe in the security arrangements.
"I trust in the measures," he said. "There will be heavy controls and the level of security will be very high. I feel safe."