When Taiwanese baseball player Chin-Lung Hu hit a single in a game against the Arizona Diamondbacks he fulfilled a promise made in a comedy sketch seventy-one years before.
Abbott and Costello’s Who’s on First? comedy sketch is perhaps the most famous routine in comedy history. If you haven’t seen the whole thing then you should stop reading now and watch it:
The premise is simple and the execution flawless. My favourite explanation comes from Principal Skinner and Superintendent Chalmers on The Simpsons:
Chalmers: Well, Seymour, it seems we’ve put together a baseball team, and I’m wondering, who’s on first?
Skinner: Yes! Not the pronoun but rather a player with the unlikely name of ‘Who’ is on first.
Chalmers: That’s just great Seymour, we’ve been out here six seconds and you’ve already managed to blow the routine.
Yes, “Who” is on first base, “What” is on second base, “I Don’t Know” is on third, and the team is rounded out by “Why,” “Today,” “Tomorrow,” and “I Don’t Give a Darn / Damn / Hoot.” Abbott tries to ascertain the names of the team members and Costello gives him the answers, each completely talking past each other to their collective growing frustration.
Similar sketches under the same premise had been performed since the 19th century, but Abbott and Costello first performed this routine together in 1936. They never performed it exactly the same way, riffing on the names, shifting the rhythms, and bouncing off each other over the course of their comedy careers.
The Taiwanese baseball player Chin-Lung Hu played his first game for the Los Angeles Dodgers in 2007. In one of those first games, against the Arizona Diamondbacks, he hit a single. This, for the first time in Major League Baseball history, put Hu on first.
The chances of a player named “I Don’t Know” are slim, but sixteen years before Abbott and Costello’s first performance of the routine the Washington Senators had a player named Allie Watt. In his one Major League game he was the team’s second baseman. In other words, Watt’s on second.
(In that same game he had just one turn at bat and hit a double, giving him a career batting average of 1.000. So in a way Watt was the greatest baseball player in history. At least in my books.)
The Generalist Academy 
Taking this one just a couple of steps further:
https://totallyrandomgarbage.blogspot.com/2021/07/whos-on-first-real-story.html