Historical clue formulations

• 1980s tennis champ Ivan — 2025-06-22
• 1980s tennis champ Ivan — 2019-07-08
• See 20-Across — 2017-07-15
• Three-time U.S. Open champ in the 1980s — 2015-05-15
• Three-time French Open champ — 2014-08-31
• Tennis great Ivan — 2013-05-01
• Three-time U.S. Open champion — 2009-12-20
• Tennis's Ivan — 2008-06-18
• McEnroe rival — 2008-02-27
• Three-time U.S. Open champ — 2007-05-22
• U.S. Open champ, 1985-87 — 2003-10-05
• Three-time U.S. Open champion — 2003-09-07
• Tennis great who never won Wimbledon — 2003-01-02
• Tennis great Ivan — 2001-10-22
• U.S. Open champ, 1985-87 — 2001-04-08
• Three-time U.S. Open winner Ivan — 2001-01-03
• U.S. Open champ, 1985-87 — 1998-12-13
• U.S. Open champ, 1985-87 — 1998-11-14