Derby head coach Paul Warne rued the loss of match-winner Nathaniel Mendez-Laing during the 1-0 win at Charlton.
Mendez-Laing has 19 goal involvements this season and hit the back of the net for the eighth time to move the Rams up to second in League One.
But he was forced off shortly after his 31st-minute strike due to a foot injury.
“It was disappointing to lose Nat, it’s a big blow for us,” said Warne.
“We’ll see how he is for next week. A stud has gone through his boot. He could’ve broke his foot, I don’t honestly know. He had a bit of blood.
“I think he should be OK. I don’t think it is too severe.”
Mendez-Laing’s injury overshadowed an otherwise straightforward day for the Rams boss.
“The lads were really good – I love a 1-0 away win,” Warne added.
“When they had to they defended well. There were some really good performances and we counter-attacked well.
“We probably could’ve done with a second goal to make it more enjoyable.
“Overall I’m buzzing. I don’t think our keeper made many saves.”
Charlton are set to appoint Nathan Jones and the former Luton, Southampton and Stoke boss watched from an executive box in the Alan Curbishley Stand.
He will inherit a side on a winless run of 12 league matches and sitting just three points above the relegation zone.
Charlton caretaker head coach Curtis Fleming – asked if he had been told that Jones was about to come in – said: “No, not really.
“I’m probably with you – we know something is going to happen.
“But until it is official then we have just got to keep plugging and going.
“He has looked at the game today and seen things I’d probably say he is happy with and also things that he will be thinking he can make a change with.
“We were causing them problems by playing directly. They didn’t really cause us a lot of problems and we had 60 per cent possession – we didn’t cause them enough problems for the areas we got into.
“The goal we gave away, it was self-inflicted. Three of the chances they had in the first half were from us.
“We spoke about the Blackpool game that they had eight chances and four of them came from us making those decisions and putting them on the front foot.
“I was disappointed with the goal. I like the way we shook ourselves off and went again, (but) we can’t keep conceding goals like that.”