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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Monday will see another fine and dry day after a cloudier start for some.
Low cloud will gradually become confined to the coast allowing sunny spells in the afternoon.
Into the evening it will remain dry with the best of the clear spells in the west.