Patrick Roberts, the subject of the chat on Saturday morning, scored his first goal since his January loan move from Manchester City as Derby twice fought back to avoid relegation and send Wednesday down.
The first half was held up for several minutes after Martyn Waghorn collided with a post when he headed wide.
Wednesday scored in the time added on after Kelle Roos saved Jordan Rhodes’ header and Sam Hutchinson pounced on the rebound.
Derby turned the game around at the start of the second half with Waghorn heading in a Tom Lawrence cross in the 49th minute before Roberts curled in from 20 yards three minutes later.
But the roller coaster ride continued when Callum Paterson fired Wednesday level in the 62nd minute after a mistake by Craig Forsyth.
Derby were in despair seven minutes later when a corner was headed back and Julian Borner turned the ball in but there was one more twist to come.
Two of Derby’s substitutes combined when Max Bird sent Kamil Jozwiak clear in the 78th minute, forcing Chey Dunkley to bring him down and Waghorn held his nerve to send the penalty into the top right corner of Keiren Westwood’s net.
Rotherham’s draw at Cardiff meant that was enough to save Derby and, although Wednesday swarmed forward, they could not find the goal that would have kept them up.
Rooney said: “I spoke to him (Patrick Roberts) this morning. We were having breakfast and I went over and said to Patrick: ‘You haven’t scored a goal all season, so today cut inside on your left foot and whip it in the top corner!
“So for him to do it, it’s great because I felt if we had that calmness there was a great opportunity for Tom Lawrence and Patrick to get into those pockets and cause problems.
“It was a crazy game and I think it’s the story of our season but the important thing is that we stayed in the division.
“My message to the players at half-time was stay calm, don’t panic, I felt we could hurt Sheffield Wednesday although I didn’t think we would come out and score two goals so quickly.
“Then again, the story of the season, we concede two very sloppy goals but Martyn (Waghorn) comes up with the penalty, there was a lot of pressure on him to step up and take a great penalty.”
Sheffield Wednesday manager Darren Moore was back in the dugout for the first time since recovering from Covid-19 and he said: “I feel a lot, lot better.
“We did a lot of tests on Wednesday, I got cleared to come here today and I felt fine to resume and get back into work.
“I said to the boys when we arrived here make sure we leave everything on the pitch and, looking at how the game went, they did that.
“We didn’t quite get there, and yes there’s disappointment, but what we have to do now is pick ourselves up and go again.
“There’s so much work ahead and there’s not a minute to be lost in terms of implementing that work and going forward.”