Historical clue formulations

• Sport on a horse — 2026-04-27
• Casual collared shirt — 2025-12-30
• Game played on horseback — 2025-11-10
• Sport with mallets — 2025-07-29
• Swimmer's response to "Marco!" — 2024-06-17
• Short-sleeved shirt — 2024-02-07
• Bit of golf attire — 2023-12-28
• Game divided into periods called chukkers — 2023-12-10
• Game played on yaks in Mongolia and Pakistan — 2023-06-23
• Sport whose players wear boots — 2023-04-30
• Sport with mallets — 2021-10-19
• Explorer Marco — 2021-10-12
• Common bit of golf attire — 2021-07-22
• Sport played at British boarding schools — 2021-03-07
• Game that can be played on bicycles or elephants — 2021-01-15
• Sport with saddles — 2020-12-27
• Water ___ — 2020-11-05
• Word with shirt or grounds — 2020-10-14
• Sport with mallets — 2020-03-30
• Standard part of preppy attire — 2020-03-06
• ___ pony — 2020-02-19
• Olympic sport discontinued after 1936 — 2019-11-14
• Game that becomes another game when its last two letters are switched — 2019-03-23
• Short-sleeved shirt — 2019-01-25
• Spiffy top — 2019-01-10
• Equestrian's sport — 2018-12-03
• Game in which it's illegal to play left-handed — 2018-06-08
• Sport last played in the Olympics in 1936 — 2018-03-25
• ___ grounds — 2017-10-15
• Summer Olympics event discontinued after 1936 — 2017-09-23
• Quarters : basketball :: chukkers : ___ — 2017-04-09
• Source for "Book of the Marvels of the World," circa 1300 — 2017-01-15
• Lacoste product — 2017-01-11
• See 16-Across — 2016-12-29
• Preppy shirt — 2016-11-22
• Casual Friday shirt — 2016-07-26
• Marco ___ (shirt sold on Rubio's website) — 2016-03-13
• Garment usually with two buttons — 2016-02-17
• Shirt style — 2015-10-11
• Common khakis go-with — 2015-07-19
• Sport with mallets — 2014-08-25
• Preppy wear — 2014-07-10
• What sport has divisions called chukkers? — 2014-06-19
• Lacoste offering — 2013-07-14
• Sport that requires helmets — 2012-10-05
• Horseplay? — 2012-06-10
• Explorer Marco — 2012-02-28
• Kind of shirt named for a sport — 2011-08-31
• Pullover shirt — 2009-11-11
• Fashion line named for a sport — 2009-08-25