Steve Carlton was actually signed directly out of Miami-Dade College by the St. Louis Cardinals while Carlton was still a 19-year old student, circumventing the draft process. Carlton received a small $4,500 bonus for his first contract, which is just as paltry as it sounds, even accounting for inflation ($34,950 in 2018).
He needed just 26 starts in the minors to tune up for major league action, making his St. Louis Cardinals debut on April 20, 1965, at the age of 20 years old and 111 days. This apperance wasn’t anything spectacular — he faced a single batter and walked him — but the road ahead of Carlton was bright.