Historical clue formulations

• Turnabout, they say — 2025-12-16
• A 40-Across will watch for it — 2012-02-10
• *Model behavior on the field — 2007-03-06
• Good sportsmanship — 2004-07-26
• Referee's demand — 2000-08-07
• Referees ensure it — 1998-10-01