Mrs Harding had been a turnstile operator at the Goldstone Ground
Sussex Police has described the arrest of a man, 24, in connection with the murder of a 73-year-old woman as a "significant breakthrough".
The body of Marie Harding was found by a dog walker on Wednesday afternoon on a footpath in Southwick, near Hove.
Sussex Police said the grandmother had been stabbed once in the neck.
Mrs Harding, 73, worked part-time at the Brighton and Hove Albion club's Queen's Road ticket office. A minute's silence was held a game on Saturday.
The man, whose name has not been released, is being questioned by detectives at a north London police station.