On January 29, 1958, Stan The Man Musial became the National League's first six figure man after inking a $100,000 deal with the St. Louis Cardinals. The reward for the 37-year-old three time MVP came after a '57 season in which he hit a league leading .351 along with 29 home runs and 102 RBI. With inflation a $100,000 today would be roughly $830,000.
The only other player to sign such a lucrative deal before Stan was the A.L.'s Splendid Splinter himself Ted Williams. Stan would go onto play until the end of the '63 season. He earned every single penny he was paid along the way. .
Musial's major league career began in the Fall of '41. According to http://www.baseball-reference.com/players/m/musiast01.shtml Stan earned $1,800 during his first stint with the Redbirds, then took home $4,500 in his first full season in '42. Baseballreference.com's final numbers have Stan's final earnings total at $980,050, which would be roughly $8 million today. Quite the steal for a player that will forever be the face of the franchise.