Major League Baseball (MLB) does not have a hard salary cap, instead employing a luxury tax which applies to teams whose total payroll exceeds certain set thresholds for a given season.
[1][2] Free agency did not exist in MLB prior to the end of the reserve clause in the 1970s, allowing owners before that time to wholly dictate the terms of player negotiations and resulting in significantly lower salaries.
Babe Ruth, widely regarded as one of the greatest baseball players ever, earned an estimated $856,850 ($19,515,718 inflation-adjusted from 1934 dollars) over his entire playing career.
[6] Kirby Puckett and Rickey Henderson signed the first contracts which paid an average of $3 million a year in November 1989.
[10] Despite this, he opted out of the remainder of his deal after the 2007 season and renegotiated a new $275 million, 10-year agreement with the Yankees, breaking his own record for the largest sports contract.