It doesn't take long for fans to make a judgement, though naysayers should be warned: it isn't always possible to tell the worth of a player after just a handful of matches. Here are ten Rams players and managers who struggled to give a good first impression but would ultimately prove the doubters wrong.
1. Gary Teale
Signing from Wigan, it took Teale a while to settle. Loans at Plymouth and Barnsley followed, before he finally got a run in the Rams' first team and a remarkable improvement in form occurred.
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2. Chris Martin
A largely disappointing loan spell didn't stop Nigel Clough signing him in 2013. Martin repaid the faith with three strong goalscoring seasons before losing his place at Pride Park.
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3. Harry Wilson
On loan from Liverpool, a slow start saw Wilson labelled lightweight and lacking an end product. Eventually, however, he became a key man in Frank Lampard's Derby side.
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4. Robbie Savage
Savage was part of the infamous Rams side relegated from the Premier League in 2008. After a loan spell away, he returned to eventually captain the side and play 137 games before retiring.
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