How did Andy Messersmith, shape the legal landscape of player's contracts, specifically as it related to the 'reverse clause?'

Andy Messersmith is most recognized by many baseball fans for his part in eliminating Major League Baseball's much-despised (save by team owners) reserve clause, allowing players to have a say in their employment status.

Step-by-step explanation

By the late summer of 1975, Messersmith and the Dodgers still hadn't reached an agreement on the terms of the following year's contract, and negotiations with the Dodgers had worsened. He filed a grievance against the Dodgers and took his case to binding arbitration after receiving guidance from the players union. Messersmith's no-trade demand could not have been the subject of arbitration because the Dodgers were under no contractual obligation to consider it. Instead, he emphasized the reserve clause, which ties a player to a team. If a player did not accept a team's contract offer, he would be forced to play under the terms of his previous deal until the organization traded or dismissed him. Because team owners agreed not to hire players who did not sign their team's annual contract offer, a player's sole option was to accept the conditions of an offered deal or leave major league baseball.

It is possible that the Dodgers were afraid of losing in arbitration and gave Messersmith a three-year deal worth $480,000. In response to the offer, Messersmith said, "I've come this far. I'll pass." I must see this through to completion. Clubs shouldn't be allowed to keep renewing player contracts year after year even if the player refuses to sign and prefers to play somewhere else. I deliberated over whether or not to do it, and ultimately decided against it, despite the fact that I am well-paid. Involuntary servitude for $115,000 a year was not something I wanted people to think about. All of that is complete nonsense. However, unless you're having issues with your owner or anything similar, this isn't for players like me who have nowhere to turn and no other option except to sue. For the guy who's on the sidelines and doesn't think he'll get a shot. 

At the end of November 1975, the arbitration was held. Dave McNally and the Montreal Expos were embroiled in a contract dispute. He was about to retire, but he decided to join Messersmith in the fight against the reserve clause.. The removal of the reserve clause, according to McNally, amounted to the players no longer being owned. 

There was a disagreement over how the word "one" was to be interpreted in Clause 10A of the standard players' agreement. If they want to extend their contract for another year, they can do so "under these same terms," according to the agreement. According to Messersmith and McNally's legal representative, Dick Moss, players' contracts could only be renewed without their agreement for a period of one year, after which time they would be free to sign with any team that desired them. According to team owner John Gaherin, an unsigned athlete can be employed by a team for as many one-year contracts as he or she like.

Baseball history will remember Messersmith and McNally for their role in ending reserve clauses on December 26, 1975, when arbitrator Peter Seitz agreed with the players that one year means one year.