Highlights
Deep Blue beat Garry Kasparov in 1997, but a random move caused by a software bug may have changed the match
Titleist Pro V1 changed golf in 2000, then courses grew longer and the sport began planning a ball-distance rollback
Pelé brought the crowds, but American soccer changed the rules: How the NASL invented five-second shootouts and banned draws
Tour de France 1904: Riders took trains, fans attacked rivals and the first four finishers were disqualified
Formula 1 put giant wings on fragile metal supports in 1969, then two crashes in Spain forced an emergency rule change