John Jensen described Denmark's 3-0 loss to Slovakia on Wednesday as the best defeat of his career, hailing his hastily assembled team as "heroes".
A row over sponsorship and commercial rights between the Danish Football Association (DBU) and players meant Denmark's established stars were not available for the friendly match in Trnava.
With head coach Age Hareide also involved in the dispute, Jensen was placed in temporary charge of a team comprising players from the Danish lower divisions and futsal sides.
They produced an admirable display against Slovakia, though, who were made to work for their victory, which came courtesy of first-half goals from Adam Nemec and Albert Rusnak, and a late own goal from Adam Fogt.
And Jensen, who had met none of the 24 players in his squad before Tuesday, confessed he was stunned at the way they competed.
"We got 24 heroes who were called in about 48 hours ago," he told a news conference. "And [they] played in a very low division compared to Slovakia, who have got world-class players.
"I'm proud, I'm shocked. These players that were on the pitch, and also these players that didn't come on the pitch, the friendship and what they did was absolutely amazing and I will never forget this defeat. This is my best defeat in my career."
It is hoped the DBU will reach an agreement with the Spillerforeningen, the Danish footballers' union, that will see their regular performers return for Sunday's UEFA Nations League match with Wales.