The singer, who has supported the Rams since he was four, was being filmed at Pride Park for a new film being made about the boy-band.
The film is being directed by Morgan Spurlock, who is the documentary maker behind Supersize Me, where he ate nothing but fast food for 30 days to see what effect it had on his health.
Niall had a kick-about on the pitch with some of his friends before the game kicked off, but no other members of the group were there.
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It will start grey and murky again with extensive low cloud. Becoming brighter with some warm sunshine later.
Turning murky again overnight. Showers possible in the south.
Walmley in the West Midlands would become the new centre of Great Britain if Scotland vote to go independent, Ordnance Survey has said.