The rampant Rams were three up by the break, Rhian Brewster volleying them into a 13th-minute lead before Ben Brereton Diaz added a second and Bobby Clark burst clear to fire past Radek Vitek.

Patrick Agyemang headed the fourth midway through the second half and Lars-Jorgen Salvesen completed the scoring when he converted a low cross from fellow substitute Andreas Weimann in the 88th minute.

Asked whether he expected to make signings over the next few days, a delighted Eustace said: “We have made it clear all along that we will only bring in players who can improve the squad.

“We have seen five players leave during the window and if we can bring in two or three then great. If not, we will go again.

“We showed tonight that we already have a great group of players, willing to work and improve. It was an excellent team performance.

“We have spoken about being better in both penalty areas and in this game we were really clinical, with five different goalscorers.

“Our first objective from the start of the season was to reach 50 points. We are now five points off that and it remains the initial target.

“There are 16 games to go, but we are progressing well towards achieving the aims of rebuilding the club and making the team really competitive in the Championship.

“We have a tight dressing room and results like this come from hard work by players and a fantastic staff on the training ground.”

City were humiliated and second to the ball for most of the 90 minutes as they suffered their heaviest home defeat since January 2010.

Head coach Gerhard Struber admitted: “From the first second to the last, in all aspects of our play, we were not ready. We deserved to lose and were not at the standard we have been this season.

“We came up against opponents with outstanding energy and we had no answer to it. We couldn’t deal with their power and didn’t bring the things to the table that we show in most games.”

Struber made no promises about adding to his squad.

“We have brought players in and it is important that we now integrate them very quickly into our style of play,” he said.

“We have received a slap in the face tonight and we have to show the resilience to respond. Our goal remains the play-offs, but we know when we look at what other clubs invest how tough a battle it is going to be.”