In 1873, three years before the National League was even formed, an 18 year old catcher named Pop Snyder played catcher for the Washington Blue Legs of the National Association.
Snyder later was a backup catcher on the 1889 Cleveland Spiders of the National League, and he backed up starting catcher Chief Zimmer.
Zimmer also caught for the 1900 Pittsburgh Pirates, which featured a shortstop named Honus Wagner.
Wagner played well into his 40s, and in 1915, was on the Pirates when Dazzy Vance made his major league debut for Pittsburgh that season.
Vance also ended up playing into his 40s, and in his last season, 1935, Dutch Leonard was a teammate of his.
Leonard was on the pitching staff of the 1947 Phillies when a bonus baby named Curt Simmons debuted at age 18 for the Phillies that year.
Simmons was a member of the 1965 Cardinals, the team that Steve Carlton broke in with...
Carlton, as I mentioned earlier, was on the 1986 Giants with Terry Mulholland...
And Mulholland played with the Twins last season, pitching to 22 year old phenom catcher Joe Mauer...
It is kind of amazing to me, that we can go from an 18 year old catcher in 1873, in the league that preceded the venerable National League, to a 22 year old catcher today in just 8 steps...