How Players Enter MLB
Most players begin their MLB careers through the amateur draft, where teams select high school and college players in a multi-round draft each year. Some international players sign directly with teams as free agents. Young drafted players typically start in minor leagues before joining their team's major league roster. Teams have rights to these drafted players for several years before the players can negotiate with other teams.
Salary Basics
All MLB players must earn at least the league minimum salary, which is set by the league and players union each season. Experienced players negotiate individual salaries based on their performance, statistics, and market demand. Star players can earn millions of dollars per year. Teams pay salaries from their revenue, and contracts are binding agreements that specify exactly how much a player will earn.
Service Time and Arbitration
Players accumulate service time based on the number of days they spend on an MLB roster. After three years of service time, players become eligible for salary arbitration, where an independent arbitrator helps determine fair pay if the player and team disagree on salary. After six years of service time, players become free agents and can negotiate with any team without restrictions. Teams can offer contracts to keep their free agents.
Contract Terms and Conditions
Beyond salary, contracts often include special terms such as signing bonuses, performance bonuses, and clause protections. No-trade clauses prevent teams from trading players without permission. Some contracts include vesting options that give players control over future years. Contracts specify what happens if a player is injured and may include details about playing time expectations or conduct standards.
Trading and Ownership Rights
Teams own the rights to their players and can trade them to other teams (unless a no-trade clause prevents it). When a player is traded, their contract moves to the new team. Teams can also release players, making them free agents available to other teams immediately. The trade deadline occurs mid-season, limiting when teams can make trades. 
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