he was the first big bonus baby!
Per wikipedia....
He was known as the "Wizard of Whiff." As an amateur—in high school, for the semipro Signal Oilers—he pitched six no-hitters, three of them in a row, and struck out 945 batters in 549 innings. In one 12-inning high school game, he struck out 27 batters.
In 1949, movie producer Frederick Stephani was looking to make a baseball movie but could not afford the story of an established star. Instead, Stephani scouted high school athletes with major league prospects, and eventually signed Pettit for $85,000. Upon his graduation in 1950, Pettit was signed by the Pittsburgh Pirates, who bought his contract from Stephani (though Stephani retained film rights), plus an additional $15,000.
So technically, i guess he got 85,000 then an additional 15,000. The equivalent of 1.126 million today