Football clubs and the definite article.
The Arsenal may now be unique, but as they evolved from Woolwich Arsenal I suppose they used to be on a par with the Villa and the Argyle, but the 'the' just stuck when they moved to Highbury and dropped the Woolwich.
Having had a manager, Arsene Wenger, with a name so similar to the club name must also be unique. If women continue to advance in the football world, perhaps one day Chelsea will have a manageress called...