Sheffield Wednesday manager Henrik Pedersen praised his side's togetherness but called it a "tough day" after they made unwanted English Football League history.
The 2-1 Steel City derby loss to Sheffield United means Wednesday have suffered the earliest ever relegation.
Going down to League One has been inevitable for most of the season but it was confirmed at Bramall Lane with 13 games remaining.
The damage was done early on as goals from Patrick Bamford and Harrison Burrows put the game beyond Wednesday on an afternoon when they needed to win to postpone their relegation.
"It was a tough day and we made the mountain bigger," Pedersen told BBC Radio Sheffield.
"Again the boys showed that they will stand together.
"They worked very hard to get back into it, we invested a lot. At 2-0 after 20 minutes you thought it could be a long day in the office today.
"The boys kept the organisation and lifted their chests up again. We changed a few things at half-time and were much stronger.
"We all believed and hoped that we could make the second goal and the boys did everything.
"The boys did everything that they could but it was not enough today."