Ultimate Soccer Manager
The original version of the game provided the English league system from the Premiership down to the Vauxhall Conferene. It was distributed as shareware, with a fully functional demo in which you could only play as then Second Division side Brighton and Hove Albion.
Came across a forum post (but lost the link) discussing old football manager games. Don't think I exaggerate when claiming myself somewhat of a connoisseur of those. I did, however, forget the title of that one demo that I spent so much time on in between Championships Manager releases.
Turns out, it was Ultimate Soccer Manager! I must’ve played the half season demo at least a couple of dozen times. That stadium expansion mechanic was absolutely ace. Felt like I was building a true empire, one half season at a time.