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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Any mist, fog and low cloud will clear to leave a mostly dry day, with sunny spells. Some scattered showers developing.
A chilly start with some mist and fog, clearing to a dry, bright day with sunny spells for most.
A Sandwell teenager has been jailed for life for killing a man and injuring another following a row over a stolen television.