Thomas Tuchel insisted Borussia Dortmund "will not forget" UEFA's decision to make them play their Champions League game against Monaco less than 24 hours after a bomb attack targeted the team bus.
A suspected Islamic extremist was arrested on Wednesday over the attack, according to German prosecutors.
The Bundesliga outfit took to the field less than 24 hours after the original tie was postponed when three explosions went off as they made their way to Signal Iduna Park, leaving defender Marc Bartra needing surgery on an arm injury.
Dortmund lost 3-2 in a breathless rearranged encounter, which Tuchel claims his side were told they had to play by a text message from UEFA.
"We were informed by text message that UEFA was making this decision," the boss told a news conference.
"A decision made in Switzerland that concerns us directly. We will not forget it, it is a very bad feeling.
"A few minutes after this attack, the only question that was asked was, 'Are you ready to play?'. As if we had thrown a beer on our coach.
"At that time, we did not know the reasons for this attack. There is a feeling of helplessness. The date was imposed on us. What we think has not interested anyone. We weren't asked about playing the game.
"We were attacked as men and we tried to solve the problem on the ground.
"Everyone has their own way of reacting to events. The players had the choice not to play but no one chose this option."
Questions were asked whether Dortmund would have been in the right frame of mind to take the field so soon after the incident.
And, after wearing T-shirts supporting their stricken team-mate in the warm-up, Dortmund's first-half performance proved doubters right as Monaco, who also missed a penalty, surged into a two-goal lead through Kylian Mbappe's opener and a Sven Bender own goal.
The second half was a different story as Ousmane Dembele and Shinji Kagawa goals either side of Mbappe's second left it all to play for ahead of the return leg in the Principality.
Dortmund midfielder Nuri Sahin, who came on as a second-half substitute, admitted football was far from his mind.
In a moving interview on Scandinavian TV, former Liverpool loanee said: "It is hard to talk about it and hard to find the right words.
"I don't know if people can understand this but until I was on the pitch in the second half I did not think about football to be honest.
"I know football is very important, we love football, we suffer with football and I know we earn a lot of money and have a privileged life but we are human beings, there is so much more than football in this world, last night we felt it.
"When I was on the bus last night, I can't forget the faces, I will never forget those faces. It was unbelievable."
Meanwhile, t he German Federal Prosecutor's Office said three similar letters claiming responsibility found near the site of the attack before the original postponed fixture on Tuesday night made an Islamic extremist motive possible.
It said that investigators had been focusing so far on two suspects from the "Islamic spectrum", both of whose apartments have been searched. One has been arrested.
A statement from the Prosecutor's Office said: "The terrorist background of the attack is based on the facts of the crime. The federal prosecutor has therefore taken the investigation. The exact motive of the attack is still unclear.
"At the site of the attack, three written claims of responsibility were found. After this an Islamic extremist background seems possible.
"Among other things the letters call for the withdrawal of Tornados from Syria and the closure of the Ramstein Air Base."
Prosecutors pointed out it was still too early to make a final decision on the motive behind the attack, but did say there were "considerable doubts about the authenticity" of another claim of responsibility, from left-wing extremists.
UEFA issued a statement in the wake of Tuchel's comments denying that either side had been forced to play.
A UEFA spokesman said: " The decision to play the UEFA Champions League match between Borussia Dortmund and AS Monaco FC on Wednesday at 18.45CET was made on Tuesday night at the BvB Stadion Dortmund in cooperation and complete agreement with clubs and authorities.
"UEFA was in touch with all parties on Wednesday and never received any information which suggested that any of the teams did not want to play."
Source: PA
