There have been instances of players leaving the course in distress.
The series included several instances of players chirping at one another and pitches thrown with a purpose.
There have been many instances of players being outstanding at a young age and, for various reasons, not making the progress expected.
The Rugby Football Union's head of sports medicine, Dr Simon Kemp, pointed out that since the PSCA was introduced, instances of players returning to the field while suffering concussion had fallen from 56%to13%3% of all diagnosed cases.
"We know beyond a shadow of a doubt that the sideline concussion protocol that we all agreed on was not given to those players," said DeMaurice Smith, the executive director of the players' union, referring to instances of players who returned to games far faster than it takes to examine them.
The N.F.L. has moved away from that set-up for several reasons, among them increased competition in the medical marketplace, and instances of players distrusting team medical staffs, said Dr. Elliot Pellman, a medical liaison to the N.F.L. and the chairman of the Jets' medical department.
Despite recent instances of players being fined, Carlisle thinks the majority would be "fantastically supportive" of an openly gay colleague now.
In 1920, Judge Landis was a leading candidate when American League and National League team owners, embarrassed by the Black Sox scandal and other instances of players throwing games, sought someone to rule over baseball.
Of the 223 instances of a player being slow to get up, 153 players were removed under the CIR (68.6%); return to play data was available for only 156/162 (96.3%) instances of the use of the CIR.
Since Yastrzemski's feat, there have been 47 instances of a player leading his league in two of the triple crown statistics.
