Three losses in a week have dropped Swansea to 13th in the table, eight points adrift of the play-off places.
Harry Wilson’s double gave Derby a two-goal lead and although Fikayo Tomori’s late own goal gave Swansea a glimmer of hope the result was never really in doubt.
Manager Graham Potter shouldered the blame after the game and a third successive defeat will undoubtedly lead to specualtion over his future at the club.
“We lacked intensity in the first half but I cannot look at the players for that, I have to look at myself,” he said at his post-match press conference.
“I have to take responsibility for that, we probably were a little too deep and too passive because of how we were set-up. And if the intensity was not there it was not because the players did not want to do it.
“Sometimes the set-up makes that happen, so that is something I have to look at and we have to look at.
“It is the third game in a week, you are not sure how to approach it in terms of what you can and cannot do but we have to think about the fact we kept going and had some opportunities.
“But as soon as the goal went in Derby were more deserving of the lead at half-time.
“We have had a bad week and that’s what football can do to you, especially in the Championship.”
Swansea’s next fixture is at Brentford on Saturday, December 8.
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